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href="/de/docs/Learn_web_development/Core/Accessibility/Tooling">Barrierefreiheitstools und unterstützende Technologien</a></li><li><a href="/de/docs/Learn_web_development/Core/Accessibility/HTML">HTML: Eine gute Grundlage für Barrierefreiheit</a></li><li><a href="/de/docs/Learn_web_development/Core/Accessibility/CSS_and_JavaScript">CSS and JavaScript Zugänglichkeitsbest Practices</a></li><li><a href="/de/docs/Learn_web_development/Core/Accessibility/WAI-ARIA_basics">WAI-ARIA Grundlagen</a></li><li><a href="/de/docs/Learn_web_development/Core/Accessibility/Multimedia">Barrierefreie Multimedia-Inhalte</a></li><li><a href="/de/docs/Learn_web_development/Core/Accessibility/Mobile">Mobile Accessibility</a></li><li><a href="/de/docs/Learn_web_development/Core/Accessibility/Accessibility_troubleshooting">Herausforderung: Barrierefreiheits-Fehlerbehebung</a></li></ol></details></li><li><a href="/de/docs/Learn_web_development/Core/Design_for_developers">Design für Entwickler:innen</a></li><li><a href="/de/docs/Learn_web_development/Core/Version_control">Versionskontrolle</a></li><li class="section"><a href="/de/docs/Learn_web_development/Extensions">Erweiterungsmodule</a></li><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects">Advanced JavaScript objects</a></summary><ol><li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes">Objektprototypen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object-oriented_programming">Objektorientierte Programmierung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript">Klassen in JavaScript</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_building_practice">Objektbaupraxis</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Adding_bouncing_balls_features">Herausforderung: Hinzufügen von Funktionen zu unserem hüpfenden Ball-Demo</a></li></ol></details></li><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Client-side_APIs">Client-seitige Web-APIs</a></summary><ol><li><a href="/de/docs/Learn_web_development/Extensions/Client-side_APIs/Introduction">Einführung in Web-APIs</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Client-side_APIs/Video_and_audio_APIs">Video- und Audio-APIs</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Client-side_APIs/Drawing_graphics">Zeichnen von Grafiken</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Client-side_APIs/Client-side_storage">Client-seitiger Speicher</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Client-side_APIs/Third_party_APIs">Third-party APIs</a></li></ol></details></li><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Async_JS">Asynchrones JavaScript</a></summary><ol><li><a href="/de/docs/Learn_web_development/Extensions/Async_JS/Introducing">Einführung in asynchrones JavaScript</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Async_JS/Promises">Anleitung zur Verwendung von Promises</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Async_JS/Implementing_a_promise-based_API">Wie man eine Promise-basierte API implementiert</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Async_JS/Introducing_workers">Einführung in Worker</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Async_JS/Sequencing_animations">Herausforderung: Animationen sequenzieren</a></li></ol></details></li><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Forms">Webformulare — Arbeiten mit Benutzerdaten</a></summary><ol><li><a href="/de/docs/Learn_web_development/Extensions/Forms/Your_first_form">Ihr erstes Formular</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Forms/How_to_structure_a_web_form">Wie man ein Webformular strukturiert</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Forms/Basic_native_form_controls">Grundlegende native Formularsteuerungen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Forms/HTML5_input_types">Die HTML5-Eingabetypen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Forms/Other_form_controls">Andere Formularelemente</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Forms/Styling_web_forms">Styling von Webformularen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Forms/Advanced_form_styling">Fortgeschrittenes Formular-Styling</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Forms/UI_pseudo-classes">UI-Pseudoklassen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Forms/Form_validation">Client-seitige Formularvalidierung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Forms/Sending_and_retrieving_form_data">Senden von Formulardaten</a></li></ol></details></li><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Client-side_tools">Verständnis für clientseitige Tools</a></summary><ol><li><a href="/de/docs/Learn_web_development/Extensions/Client-side_tools/Overview">Überblick über Client-seitige Tools</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Client-side_tools/Package_management">Grundlagen des Paketmanagements</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Client-side_tools/Introducing_complete_toolchain">Einführung in eine vollständige Werkzeugkette</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Client-side_tools/Deployment">Bereitstellung unserer App</a></li></ol></details></li><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Server-side">Serverseitige Programmierung</a></summary><ol><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Server-side/First_steps">Erste Schritte auf der Serverseite</a></summary><ol><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/First_steps/Introduction">Einführung in die Server-Seite</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/First_steps/Client-Server_overview">Überblick über Client-Server</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/First_steps/Web_frameworks">Server-seitige Web-Frameworks</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/First_steps/Website_security">Website-Sicherheit</a></li></ol></details></li><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django">Django Web-Framework (Python)</a></summary><ol><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Introduction">Einführung in Django</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/development_environment">Einrichten einer Django-Entwicklungsumgebung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Tutorial_local_library_website">Django Tutorial: Die Website der lokalen Bibliothek</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/skeleton_website">Django-Tutorial Teil 2: Erstellen einer Skelett-Website</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Models">Django Tutorial Teil 3: Verwenden von Modellen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Admin_site">Django Tutorial Teil 4: Die Django Admin-Seite</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Home_page">Django Tutorial Teil 5: Erstellen unserer Homepage</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Generic_views">Django Tutorial Teil 6: Generische Listen- und Detailansichten</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Sessions">Django-Tutorial Teil 7: Sitzungs-Framework</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Authentication">Django-Tutorial Teil 8: Benutzer-Authentifizierung und -Berechtigungen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Forms">Django Tutorial Teil 9: Arbeiten mit Formularen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Testing">Django Tutorial Teil 10: Testen einer Django-Webanwendung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/Deployment">Django-Tutorial Teil 11: Bereitstellung von Django für die Produktion</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/web_application_security">Django Webanwendungssicherheit</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Django/django_assessment_blog">Bewertung: DIY Django Mini-Blog</a></li></ol></details></li><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs">Express Web-Framework (Node.js)</a></summary><ol><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Introduction">Einführung in Express/Node</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/development_environment">Einrichten einer Node-Entwicklungsumgebung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Tutorial_local_library_website">Express Tutorial: Die Website der lokalen Bibliothek</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/skeleton_website">Express-Tutorial Teil 2: Erstellen einer Skelett-Website</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/mongoose">Express-Tutorial Teil 3: Verwendung einer Datenbank (mit Mongoose)</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/routes">Express Tutorial Teil 4: Routen und Controller</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Displaying_data">Express Tutorial Teil 5: Bibliotheksdaten anzeigen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/forms">Express Tutorial Teil 6: Arbeiten mit Formularen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/deployment">Express Tutorial Teil 7: Bereitstellung im Produktionsumfeld</a></li></ol></details></li></ol></details></li><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Performance">Web-Performance</a></summary><ol><li><a href="/de/docs/Learn_web_development/Extensions/Performance/why_web_performance">Das "Warum" der Web-Performance</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Performance/What_is_web_performance">Was ist Web-Performance?</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Performance/Perceived_performance">Wahrgenommene Leistung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Performance/Measuring_performance">Leistungsmessung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Performance/Multimedia">Multimedia: Bilder</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Performance/video">Multimedia: video</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Performance/JavaScript">JavaScript-Leistungsoptimierung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Performance/HTML">HTML-Performance-Optimierung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Performance/CSS">CSS-Leistungsoptimierung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Performance/business_case_for_performance">Der geschäftliche Nutzen der Web-Performance</a></li></ol></details></li><li class="toggle"><details><summary><a href="/de/docs/Learn_web_development/Extensions/Testing">Tests</a></summary><ol><li><a href="/de/docs/Learn_web_development/Extensions/Testing/Introduction">Einführung in das Cross-Browser-Testing</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Testing/Testing_strategies">Strategien zur Durchführung von Tests</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Testing/HTML_and_CSS">Umgang mit häufigen HTML- und CSS-Problemen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Testing/Feature_detection">Implementierung der Funktionsprüfung</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Testing/Automated_testing">Einführung in automatisiertes Testen</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Testing/Your_own_automation_environment">Einrichtung Ihrer eigenen Testautomatisierungsumgebung</a></li></ol></details></li><li><a href="/de/docs/Learn_web_development/Extensions/Transform_animate">CSS transformieren und animieren</a></li><li><a href="/de/docs/Learn_web_development/Extensions/Security_privacy">Sicherheit und Datenschutz</a></li><li class="section">Weitere Ressourcen</li><li class="toggle"><details open=""><summary><a href="/de/docs/Learn_web_development/Howto">Häufige Probleme lösen</a></summary><ol><li><a href="/de/docs/Learn_web_development/Howto/Solve_HTML_problems">Häufige HTML-Probleme lösen</a></li><li><a href="/de/docs/Learn_web_development/Howto/Solve_CSS_problems">Häufige CSS-Probleme lösen</a></li><li><em><a href="/de/docs/Learn_web_development/Howto/Solve_JavaScript_problems" aria-current="page">Häufige JavaScript-Probleme lösen</a></em></li><li><a href="/de/docs/Learn_web_development/Howto/Web_mechanics">Webmechanik</a></li><li><a href="/de/docs/Learn_web_development/Howto/Tools_and_setup">Tools und Einrichtung</a></li><li><a href="/de/docs/Learn_web_development/Howto/Design_and_accessibility">Design und Barrierefreiheit</a></li></ol></details></li><li><a href="/de/docs/Learn_web_development/About">Über</a></li><li><a href="/de/docs/Learn_web_development/Educators">Ressourcen für Lehrkräfte</a></li><li><a href="/de/docs/Learn_web_development/Changelog">Änderungsprotokoll</a></li></ol></div></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In diesem Artikel</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#häufige_anfängerfehler">Häufige Anfängerfehler</a></li><li class="document-toc-item "><a class="document-toc-link" href="#grundlegende_definitionen">Grundlegende Definitionen</a></li><li class="document-toc-item "><a class="document-toc-link" href="#grundlegende_anwendungsfälle">Grundlegende Anwendungsfälle</a></li><li class="document-toc-item "><a class="document-toc-link" href="#mittelstufe_anwendungsfälle">Mittelstufe Anwendungsfälle</a></li></ul></section></div></nav></aside><section class="place side"></section></div></div><main id="content" class="main-content "><article class="main-page-content" lang="de"><header><h1>Häufige JavaScript-Probleme lösen</h1></header><div class="section-content"><p>Die folgenden Links verweisen auf Lösungen für häufige Probleme, die bei der Programmierung mit JavaScript auftreten können.</p></div><section aria-labelledby="häufige_anfängerfehler"><h2 id="häufige_anfängerfehler"><a href="#häufige_anfängerfehler">Häufige Anfängerfehler</a></h2><div class="section-content"></div></section><section aria-labelledby="korrekte_schreibweise_und_groß-kleinschreibung"><h3 id="korrekte_schreibweise_und_groß-kleinschreibung"><a href="#korrekte_schreibweise_und_groß-kleinschreibung">Korrekte Schreibweise und Groß-/Kleinschreibung</a></h3><div class="section-content"><p>Wenn Ihr Code nicht funktioniert und/oder der Browser meldet, dass etwas undefiniert ist, überprüfen Sie, ob Sie alle Variablennamen, Funktionsnamen usw. korrekt geschrieben haben.</p> <p>Einige häufig verwendete integrierte Browserfunktionen, die Probleme verursachen, sind:</p> <figure class="table-container"><table> <thead> <tr> <th>Richtig</th> <th>Falsch</th> </tr> </thead> <tbody> <tr> <td><code>getElementsByTagName()</code></td> <td><code>getElementByTagName()</code></td> </tr> <tr> <td><code>getElementsByName()</code></td> <td><code>getElementByName()</code></td> </tr> <tr> <td><code>getElementsByClassName()</code></td> <td><code>getElementByClassName()</code></td> </tr> <tr> <td><code>getElementById()</code></td> <td><code>getElementsById()</code></td> </tr> </tbody> </table></figure></div></section><section aria-labelledby="position_des_semikolons"><h3 id="position_des_semikolons"><a href="#position_des_semikolons">Position des Semikolons</a></h3><div class="section-content"><p>Stellen Sie sicher, dass Sie keine Semikolons an falschen Stellen setzen. Zum Beispiel:</p> <figure class="table-container"><table> <thead> <tr> <th>Richtig</th> <th>Falsch</th> </tr> </thead> <tbody> <tr> <td><code>elem.style.color = 'red';</code></td> <td><code>elem.style.color = 'red;'</code></td> </tr> </tbody> </table></figure></div></section><section aria-labelledby="funktionen"><h3 id="funktionen"><a href="#funktionen">Funktionen</a></h3><div class="section-content"><p>Es gibt mehrere Dinge, die bei Funktionen schiefgehen können.</p> <p>Ein häufiger Fehler ist es, die Funktion zu deklarieren, sie jedoch nirgendwo aufzurufen. Zum Beispiel:</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>function myFunction() { alert("This is my function."); } </code></pre></div> <p>Dieser Code wird nichts tun, es sei denn, Sie rufen ihn mit der folgenden Anweisung auf:</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>myFunction(); </code></pre></div> <h4 id="funktionsbereich">Funktionsbereich</h4> <p>Denken Sie daran, dass <a href="/de/docs/Learn_web_development/Core/Scripting/Functions#function_scope_and_conflicts">Funktionen ihren eigenen Gültigkeitsbereich haben</a> – Sie können von außerhalb der Funktion nicht auf eine innerhalb der Funktion gesetzte Variable zugreifen, es sei denn, Sie haben die Variable global deklariert (d. h. nicht innerhalb einer Funktion) oder <a href="/de/docs/Learn_web_development/Core/Scripting/Return_values">den Wert aus der Funktion zurückgegeben</a>.</p> <h4 id="ausführen_von_code_nach_einer_return-anweisung">Ausführen von Code nach einer return-Anweisung</h4> <p>Beachten Sie auch, dass der JavaScript-Interpreter die Funktion verlässt, wenn Sie eine return-Anweisung ausführen – kein Code nach der return-Anweisung wird ausgeführt.</p> <p>Tatsächlich geben einige Browser (wie Firefox) Ihnen eine Fehlermeldung in der Entwicklerkonsole, wenn Sie Code nach einer return-Anweisung haben. Firefox gibt: "unreachable code after return statement".</p></div></section><section aria-labelledby="objektnotation_versus_normale_zuweisung"><h3 id="objektnotation_versus_normale_zuweisung"><a href="#objektnotation_versus_normale_zuweisung">Objektnotation versus normale Zuweisung</a></h3><div class="section-content"><p>Wenn Sie in JavaScript normalerweise etwas zuweisen, verwenden Sie ein einzelnes Gleichheitszeichen, z. B.:</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>const myNumber = 0; </code></pre></div> <p>Bei <a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects">Objekten</a> müssen Sie jedoch darauf achten, die korrekte Syntax zu verwenden. Das Objekt muss von geschweiften Klammern umgeben sein, die Mitgliedsnamen müssen durch Doppelpunkte von ihren Werten getrennt sein und die Mitglieder müssen durch Kommas getrennt sein. Zum Beispiel:</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>const myObject = { name: "Chris", age: 38, }; </code></pre></div></div></section><section aria-labelledby="grundlegende_definitionen"><h2 id="grundlegende_definitionen"><a href="#grundlegende_definitionen">Grundlegende Definitionen</a></h2><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/What_is_JavaScript#a_high-level_definition">Was ist JavaScript?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Variables#what_is_a_variable">Was ist eine Variable?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Strings">Was sind Strings?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Arrays#what_is_an_array">Was ist ein Array?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Loops">Was ist eine Schleife?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Functions">Was ist eine Funktion?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Events">Was ist ein Ereignis?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Object_basics#object_basics">Was ist ein Objekt?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/JSON#no_really_what_is_json">Was ist JSON?</a></li> <li><a href="/de/docs/Learn_web_development/Extensions/Client-side_APIs/Introduction#what_are_apis">Was ist eine Web-API?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/DOM_scripting#the_document_object_model">Was ist das DOM?</a></li> </ul></div></section><section aria-labelledby="grundlegende_anwendungsfälle"><h2 id="grundlegende_anwendungsfälle"><a href="#grundlegende_anwendungsfälle">Grundlegende Anwendungsfälle</a></h2><div class="section-content"></div></section><section aria-labelledby="allgemein"><h3 id="allgemein"><a href="#allgemein">Allgemein</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/What_is_JavaScript#how_do_you_add_javascript_to_your_page">Wie fügt man einer Seite JavaScript hinzu?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/What_is_JavaScript#comments">Wie fügt man Kommentare zum JavaScript-Code hinzu?</a></li> </ul></div></section><section aria-labelledby="variablen"><h3 id="variablen"><a href="#variablen">Variablen</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Variables#declaring_a_variable">Wie deklariert man eine Variable?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Variables#initializing_a_variable">Wie initialisiert man eine Variable mit einem Wert?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Variables#updating_a_variable">Wie aktualisiert man den Wert einer Variable?</a> (siehe auch <a href="/de/docs/Learn_web_development/Core/Scripting/Math#assignment_operators">Zuweisungsoperatoren</a>)</li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Variables#variable_types">Welche Datentypen können Werte in JavaScript haben?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Variables#dynamic_typing">Was bedeutet 'lose typisiert'?</a></li> </ul></div></section><section aria-labelledby="mathematik"><h3 id="mathematik"><a href="#mathematik">Mathematik</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Math#types_of_numbers">Mit welchen Typen von Zahlen hat man in der Webentwicklung zu tun?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Math#arithmetic_operators">Wie macht man grundlegende Mathematik in JavaScript?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Math#operator_precedence">Was ist Operator-Präzedenz, und wie wird sie in JavaScript gehandhabt?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Math#increment_and_decrement_operators">Wie erhöht oder verringert man Werte in JavaScript?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Math#comparison_operators">Wie vergleicht man Werte in JavaScript?</a> (z. B. um zu sehen, welcher größer ist, oder ob ein Wert gleich einem anderen ist).</li> </ul></div></section><section aria-labelledby="strings"><h3 id="strings"><a href="#strings">Strings</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Strings#creating_a_string">Wie erstellt man einen String in JavaScript?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Strings#single_quotes_vs._double_quotes">Muss man einfache oder doppelte Anführungszeichen verwenden?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Strings#escaping_characters_in_a_string">Wie entkommt man Zeichen in Strings?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Strings#concatenating_strings">Wie verbindet man Strings miteinander?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Strings#numbers_vs._strings">Kann man Strings und Zahlen miteinander verbinden?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods#finding_the_length_of_a_string">Wie ermittelt man die Länge eines Strings?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods#retrieving_a_specific_string_character">Wie findet man heraus, welches Zeichen an einer bestimmten Position in einem String ist?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods#extracting_a_substring_from_a_string">Wie findet und extrahiert man eine bestimmte Teilzeichenfolge aus einem String?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods#changing_case">Wie ändert man die Groß-/Kleinschreibung eines Strings?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods#updating_parts_of_a_string">Wie ersetzt man eine spezifische Teilzeichenfolge durch eine andere?</a></li> </ul></div></section><section aria-labelledby="arrays"><h3 id="arrays"><a href="#arrays">Arrays</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Arrays#creating_arrays">Wie erstellt man ein Array?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Arrays#accessing_and_modifying_array_items">Wie greift man auf die Elemente eines Arrays zu und modifiziert diese?</a> (dies umfasst auch mehrdimensionale Arrays)</li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Arrays#finding_the_length_of_an_array">Wie ermittelt man die Länge eines Arrays?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Arrays#adding_items">Wie fügt man Elemente zu einem Array hinzu?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Arrays#removing_items">Wie entfernt man Elemente aus einem Array?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Arrays#converting_between_strings_and_arrays">Wie splittet man einen String in Array-Elemente oder verbindet Array-Elemente in einen String?</a></li> </ul></div></section><section aria-labelledby="javascript_debuggen"><h3 id="javascript_debuggen"><a href="#javascript_debuggen">JavaScript debuggen</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/What_went_wrong#types_of_error">Was sind die grundlegenden Arten von Fehlern?</a></li> <li><a href="/de/docs/Learn_web_development/Howto/Tools_and_setup/What_are_browser_developer_tools">Was sind Browser-Entwicklertools und wie greift man darauf zu?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript#the_console_api">Wie loggt man einen Wert in die JavaScript-Konsole?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript#using_the_javascript_debugger">Wie verwendet man Breakpoints und andere JavaScript-Debugging-Funktionen?</a></li> </ul> <p>Für weitere Informationen über das Debuggen von JavaScript, siehe <a href="/de/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript">Umgang mit häufigen JavaScript-Problemen</a>. Siehe auch <a href="/de/docs/Learn_web_development/Core/Scripting/What_went_wrong#other_common_errors">Andere häufige Fehler</a> für eine Beschreibung häufiger Fehler.</p></div></section><section aria-labelledby="entscheidungen_im_code_treffen"><h3 id="entscheidungen_im_code_treffen"><a href="#entscheidungen_im_code_treffen">Entscheidungen im Code treffen</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Conditionals">Wie führt man verschiedene Code-Blöcke aus, abhängig vom Wert einer Variable oder einer anderen Bedingung?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Conditionals#if...else_statements">Wie verwendet man if...else Anweisungen?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Conditionals#nesting_if...else">Wie verschachtelt man einen Entscheidungsblock in einem anderen?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Conditionals#logical_operators_and_or_and_not">Wie verwendet man UND, ODER, und NICHT Operatoren in JavaScript?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Conditionals#switch_statements">Wie behandelt man bequem eine große Anzahl von Auswahlmöglichkeiten für eine Bedingung?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Conditionals#ternary_operator">Wie verwendet man einen ternären Operator, um schnell zwischen zwei Optionen zu wählen, basierend auf einem True- oder False-Test?</a></li> </ul></div></section><section aria-labelledby="schleifeniteration"><h3 id="schleifeniteration"><a href="#schleifeniteration">Schleifen/Iteration</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Loops">Wie führt man denselben Codeabschnitt immer wieder aus?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Loops#exiting_loops_with_break">Wie verlässt man eine Schleife vorzeitig, wenn eine bestimmte Bedingung erfüllt ist?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Loops#skipping_iterations_with_continue">Wie überspringt man zur nächsten Iteration einer Schleife, wenn eine bestimmte Bedingung erfüllt ist?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Loops#while_and_do_..._while">Wie verwendet man while und do...while Schleifen?</a></li> </ul></div></section><section aria-labelledby="mittelstufe_anwendungsfälle"><h2 id="mittelstufe_anwendungsfälle"><a href="#mittelstufe_anwendungsfälle">Mittelstufe Anwendungsfälle</a></h2><div class="section-content"></div></section><section aria-labelledby="funktionen_2"><h3 id="funktionen_2"><a href="#funktionen_2">Funktionen</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Functions#built-in_browser_functions">Wie findet man Funktionen im Browser?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Functions#functions_versus_methods">Was ist der Unterschied zwischen einer Funktion und einer Methode?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Build_your_own_function">Wie erstellt man eigene Funktionen?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Functions#invoking_functions">Wie führt man eine Funktion aus (aufrufen oder auslösen)?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Functions#anonymous_functions">Was ist eine anonyme Funktion?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Functions#function_parameters">Wie gibt man Parameter (oder Argumente) an, wenn man eine Funktion aufruft?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Functions#function_scope_and_conflicts">Was ist der Funktionsbereich?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Return_values">Was sind Rückgabewerte, und wie verwendet man sie?</a></li> </ul></div></section><section aria-labelledby="objekte"><h3 id="objekte"><a href="#objekte">Objekte</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Object_basics#object_basics">Wie erstellt man ein Objekt?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Object_basics#dot_notation">Was ist Punktnotation?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Object_basics#bracket_notation">Was ist Klammernotation?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Object_basics#setting_object_members">Wie erhält und setzt man die Methoden und Eigenschaften eines Objekts?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Object_basics#what_is_this">Was ist <code>this</code> im Kontext eines Objekts?</a></li> <li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript#object-oriented_programming_from_10000_meters">Was ist objektorientierte Programmierung?</a></li> <li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript#constructors_and_object_instances">Was sind Konstruktoren und Instanzen, und wie erstellt man sie?</a></li> <li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript#other_ways_to_create_object_instances">Welche verschiedenen Möglichkeiten gibt es, Objekte in JavaScript zu erstellen?</a></li> </ul></div></section><section aria-labelledby="json"><h3 id="json"><a href="#json">JSON</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/JSON#json_structure">Wie strukturiert man JSON-Daten und liest sie in JavaScript ein?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/JSON#loading_our_json">Wie kann man eine JSON-Datei in eine Seite laden?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/JSON#converting_between_objects_and_text">Wie konvertiert man ein JSON-Objekt in einen Textstring und zurück?</a></li> </ul></div></section><section aria-labelledby="events"><h3 id="events"><a href="#events">Events</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Events#event_handler_properties">Was sind Event-Handler und wie benutzt man sie?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Events#inline_event_handlers_%e2%80%94_don%27t_use_these">Was sind Inline-Event-Handler?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Events#using_addeventlistener">Was macht die <code>addEventListener()</code>-Funktion und wie benutzt man sie?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Events#what_mechanism_should_i_use">Welchen Mechanismus sollte ich verwenden, um Event-Code zu meinen Webseiten hinzuzufügen?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Events#event_objects">Was sind Event-Objekte und wie verwendet man sie?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Events#preventing_default_behavior">Wie verhindert man das standardmäßige Verhalten eines Events?</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Event_bubbling">Wie feuern Events auf verschachtelten Elementen ab? (Event-Propagation, auch zugehörig — Event-Bubbling und -Capturing)</a></li> <li><a href="/de/docs/Learn_web_development/Core/Scripting/Event_bubbling#event_delegation">Was ist Event-Delegation und wie funktioniert sie?</a></li> </ul></div></section><section aria-labelledby="objektorientiertes_javascript"><h3 id="objektorientiertes_javascript"><a href="#objektorientiertes_javascript">Objektorientiertes JavaScript</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes">Was sind Objektprototypen?</a></li> <li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes#the_constructor_property">Was ist die constructor-Eigenschaft und wie kann man sie verwenden?</a></li> <li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes#modifying_prototypes">Wie fügt man Methoden zum Konstruktor hinzu?</a></li> <li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript">Wie erstellt man einen neuen Konstruktor, der seine Mitglieder von einem Eltern-Konstruktor erbt?</a></li> <li><a href="/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript#object_member_summary">Wann sollte man Vererbung in JavaScript verwenden?</a></li> </ul></div></section><section aria-labelledby="web-apis"><h3 id="web-apis"><a href="#web-apis">Web-APIs</a></h3><div class="section-content"><ul> <li><a href="/de/docs/Learn_web_development/Core/Scripting/DOM_scripting#active_learning_basic_dom_manipulation">Wie manipuliert man das DOM (z.B. 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contributors. Content available under <a href="/de/docs/MDN/Writing_guidelines/Attrib_copyright_license">a Creative Commons license</a>.</p></div></div></footer></div><script type="application/json" id="hydration">{"url":"/de/docs/Learn_web_development/Howto/Solve_JavaScript_problems","doc":{"body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<p>Die folgenden Links verweisen auf Lösungen für häufige Probleme, die bei der Programmierung mit JavaScript auftreten können.</p>"}},{"type":"prose","value":{"id":"häufige_anfängerfehler","title":"Häufige Anfängerfehler","isH3":false,"content":""}},{"type":"prose","value":{"id":"korrekte_schreibweise_und_groß-kleinschreibung","title":"Korrekte Schreibweise und Groß-/Kleinschreibung","isH3":true,"content":"<p>Wenn Ihr Code nicht funktioniert und/oder der Browser meldet, dass etwas undefiniert ist, überprüfen Sie, ob Sie alle Variablennamen, Funktionsnamen usw. korrekt geschrieben haben.</p>\n<p>Einige häufig verwendete integrierte Browserfunktionen, die Probleme verursachen, sind:</p>\n<figure class=\"table-container\"><table>\n<thead>\n<tr>\n<th>Richtig</th>\n<th>Falsch</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>getElementsByTagName()</code></td>\n<td><code>getElementByTagName()</code></td>\n</tr>\n<tr>\n<td><code>getElementsByName()</code></td>\n<td><code>getElementByName()</code></td>\n</tr>\n<tr>\n<td><code>getElementsByClassName()</code></td>\n<td><code>getElementByClassName()</code></td>\n</tr>\n<tr>\n<td><code>getElementById()</code></td>\n<td><code>getElementsById()</code></td>\n</tr>\n</tbody>\n</table></figure>"}},{"type":"prose","value":{"id":"position_des_semikolons","title":"Position des Semikolons","isH3":true,"content":"<p>Stellen Sie sicher, dass Sie keine Semikolons an falschen Stellen setzen. Zum Beispiel:</p>\n<figure class=\"table-container\"><table>\n<thead>\n<tr>\n<th>Richtig</th>\n<th>Falsch</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>elem.style.color = 'red';</code></td>\n<td><code>elem.style.color = 'red;'</code></td>\n</tr>\n</tbody>\n</table></figure>"}},{"type":"prose","value":{"id":"funktionen","title":"Funktionen","isH3":true,"content":"<p>Es gibt mehrere Dinge, die bei Funktionen schiefgehen können.</p>\n<p>Ein häufiger Fehler ist es, die Funktion zu deklarieren, sie jedoch nirgendwo aufzurufen. Zum Beispiel:</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>function myFunction() {\n alert(\"This is my function.\");\n}\n</code></pre></div>\n<p>Dieser Code wird nichts tun, es sei denn, Sie rufen ihn mit der folgenden Anweisung auf:</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>myFunction();\n</code></pre></div>\n<h4 id=\"funktionsbereich\">Funktionsbereich</h4>\n<p>Denken Sie daran, dass <a href=\"/de/docs/Learn_web_development/Core/Scripting/Functions#function_scope_and_conflicts\">Funktionen ihren eigenen Gültigkeitsbereich haben</a> – Sie können von außerhalb der Funktion nicht auf eine innerhalb der Funktion gesetzte Variable zugreifen, es sei denn, Sie haben die Variable global deklariert (d. h. nicht innerhalb einer Funktion) oder <a href=\"/de/docs/Learn_web_development/Core/Scripting/Return_values\">den Wert aus der Funktion zurückgegeben</a>.</p>\n<h4 id=\"ausführen_von_code_nach_einer_return-anweisung\">Ausführen von Code nach einer return-Anweisung</h4>\n<p>Beachten Sie auch, dass der JavaScript-Interpreter die Funktion verlässt, wenn Sie eine return-Anweisung ausführen – kein Code nach der return-Anweisung wird ausgeführt.</p>\n<p>Tatsächlich geben einige Browser (wie Firefox) Ihnen eine Fehlermeldung in der Entwicklerkonsole, wenn Sie Code nach einer return-Anweisung haben. Firefox gibt: \"unreachable code after return statement\".</p>"}},{"type":"prose","value":{"id":"objektnotation_versus_normale_zuweisung","title":"Objektnotation versus normale Zuweisung","isH3":true,"content":"<p>Wenn Sie in JavaScript normalerweise etwas zuweisen, verwenden Sie ein einzelnes Gleichheitszeichen, z. B.:</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>const myNumber = 0;\n</code></pre></div>\n<p>Bei <a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects\">Objekten</a> müssen Sie jedoch darauf achten, die korrekte Syntax zu verwenden. Das Objekt muss von geschweiften Klammern umgeben sein, die Mitgliedsnamen müssen durch Doppelpunkte von ihren Werten getrennt sein und die Mitglieder müssen durch Kommas getrennt sein. Zum Beispiel:</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>const myObject = {\n name: \"Chris\",\n age: 38,\n};\n</code></pre></div>"}},{"type":"prose","value":{"id":"grundlegende_definitionen","title":"Grundlegende Definitionen","isH3":false,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/What_is_JavaScript#a_high-level_definition\">Was ist JavaScript?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Variables#what_is_a_variable\">Was ist eine Variable?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Strings\">Was sind Strings?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Arrays#what_is_an_array\">Was ist ein Array?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Loops\">Was ist eine Schleife?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Functions\">Was ist eine Funktion?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Events\">Was ist ein Ereignis?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Object_basics#object_basics\">Was ist ein Objekt?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/JSON#no_really_what_is_json\">Was ist JSON?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_APIs/Introduction#what_are_apis\">Was ist eine Web-API?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/DOM_scripting#the_document_object_model\">Was ist das DOM?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"grundlegende_anwendungsfälle","title":"Grundlegende Anwendungsfälle","isH3":false,"content":""}},{"type":"prose","value":{"id":"allgemein","title":"Allgemein","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/What_is_JavaScript#how_do_you_add_javascript_to_your_page\">Wie fügt man einer Seite JavaScript hinzu?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/What_is_JavaScript#comments\">Wie fügt man Kommentare zum JavaScript-Code hinzu?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"variablen","title":"Variablen","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Variables#declaring_a_variable\">Wie deklariert man eine Variable?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Variables#initializing_a_variable\">Wie initialisiert man eine Variable mit einem Wert?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Variables#updating_a_variable\">Wie aktualisiert man den Wert einer Variable?</a> (siehe auch <a href=\"/de/docs/Learn_web_development/Core/Scripting/Math#assignment_operators\">Zuweisungsoperatoren</a>)</li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Variables#variable_types\">Welche Datentypen können Werte in JavaScript haben?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Variables#dynamic_typing\">Was bedeutet 'lose typisiert'?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"mathematik","title":"Mathematik","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Math#types_of_numbers\">Mit welchen Typen von Zahlen hat man in der Webentwicklung zu tun?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Math#arithmetic_operators\">Wie macht man grundlegende Mathematik in JavaScript?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Math#operator_precedence\">Was ist Operator-Präzedenz, und wie wird sie in JavaScript gehandhabt?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Math#increment_and_decrement_operators\">Wie erhöht oder verringert man Werte in JavaScript?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Math#comparison_operators\">Wie vergleicht man Werte in JavaScript?</a> (z. B. um zu sehen, welcher größer ist, oder ob ein Wert gleich einem anderen ist).</li>\n</ul>"}},{"type":"prose","value":{"id":"strings","title":"Strings","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Strings#creating_a_string\">Wie erstellt man einen String in JavaScript?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Strings#single_quotes_vs._double_quotes\">Muss man einfache oder doppelte Anführungszeichen verwenden?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Strings#escaping_characters_in_a_string\">Wie entkommt man Zeichen in Strings?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Strings#concatenating_strings\">Wie verbindet man Strings miteinander?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Strings#numbers_vs._strings\">Kann man Strings und Zahlen miteinander verbinden?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods#finding_the_length_of_a_string\">Wie ermittelt man die Länge eines Strings?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods#retrieving_a_specific_string_character\">Wie findet man heraus, welches Zeichen an einer bestimmten Position in einem String ist?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods#extracting_a_substring_from_a_string\">Wie findet und extrahiert man eine bestimmte Teilzeichenfolge aus einem String?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods#changing_case\">Wie ändert man die Groß-/Kleinschreibung eines Strings?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods#updating_parts_of_a_string\">Wie ersetzt man eine spezifische Teilzeichenfolge durch eine andere?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"arrays","title":"Arrays","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Arrays#creating_arrays\">Wie erstellt man ein Array?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Arrays#accessing_and_modifying_array_items\">Wie greift man auf die Elemente eines Arrays zu und modifiziert diese?</a> (dies umfasst auch mehrdimensionale Arrays)</li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Arrays#finding_the_length_of_an_array\">Wie ermittelt man die Länge eines Arrays?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Arrays#adding_items\">Wie fügt man Elemente zu einem Array hinzu?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Arrays#removing_items\">Wie entfernt man Elemente aus einem Array?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Arrays#converting_between_strings_and_arrays\">Wie splittet man einen String in Array-Elemente oder verbindet Array-Elemente in einen String?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"javascript_debuggen","title":"JavaScript debuggen","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/What_went_wrong#types_of_error\">Was sind die grundlegenden Arten von Fehlern?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Howto/Tools_and_setup/What_are_browser_developer_tools\">Was sind Browser-Entwicklertools und wie greift man darauf zu?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript#the_console_api\">Wie loggt man einen Wert in die JavaScript-Konsole?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript#using_the_javascript_debugger\">Wie verwendet man Breakpoints und andere JavaScript-Debugging-Funktionen?</a></li>\n</ul>\n<p>Für weitere Informationen über das Debuggen von JavaScript, siehe <a href=\"/de/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript\">Umgang mit häufigen JavaScript-Problemen</a>. Siehe auch <a href=\"/de/docs/Learn_web_development/Core/Scripting/What_went_wrong#other_common_errors\">Andere häufige Fehler</a> für eine Beschreibung häufiger Fehler.</p>"}},{"type":"prose","value":{"id":"entscheidungen_im_code_treffen","title":"Entscheidungen im Code treffen","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Conditionals\">Wie führt man verschiedene Code-Blöcke aus, abhängig vom Wert einer Variable oder einer anderen Bedingung?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Conditionals#if...else_statements\">Wie verwendet man if...else Anweisungen?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Conditionals#nesting_if...else\">Wie verschachtelt man einen Entscheidungsblock in einem anderen?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Conditionals#logical_operators_and_or_and_not\">Wie verwendet man UND, ODER, und NICHT Operatoren in JavaScript?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Conditionals#switch_statements\">Wie behandelt man bequem eine große Anzahl von Auswahlmöglichkeiten für eine Bedingung?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Conditionals#ternary_operator\">Wie verwendet man einen ternären Operator, um schnell zwischen zwei Optionen zu wählen, basierend auf einem True- oder False-Test?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"schleifeniteration","title":"Schleifen/Iteration","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Loops\">Wie führt man denselben Codeabschnitt immer wieder aus?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Loops#exiting_loops_with_break\">Wie verlässt man eine Schleife vorzeitig, wenn eine bestimmte Bedingung erfüllt ist?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Loops#skipping_iterations_with_continue\">Wie überspringt man zur nächsten Iteration einer Schleife, wenn eine bestimmte Bedingung erfüllt ist?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Loops#while_and_do_..._while\">Wie verwendet man while und do...while Schleifen?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"mittelstufe_anwendungsfälle","title":"Mittelstufe Anwendungsfälle","isH3":false,"content":""}},{"type":"prose","value":{"id":"funktionen_2","title":"Funktionen","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Functions#built-in_browser_functions\">Wie findet man Funktionen im Browser?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Functions#functions_versus_methods\">Was ist der Unterschied zwischen einer Funktion und einer Methode?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Build_your_own_function\">Wie erstellt man eigene Funktionen?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Functions#invoking_functions\">Wie führt man eine Funktion aus (aufrufen oder auslösen)?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Functions#anonymous_functions\">Was ist eine anonyme Funktion?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Functions#function_parameters\">Wie gibt man Parameter (oder Argumente) an, wenn man eine Funktion aufruft?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Functions#function_scope_and_conflicts\">Was ist der Funktionsbereich?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Return_values\">Was sind Rückgabewerte, und wie verwendet man sie?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"objekte","title":"Objekte","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Object_basics#object_basics\">Wie erstellt man ein Objekt?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Object_basics#dot_notation\">Was ist Punktnotation?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Object_basics#bracket_notation\">Was ist Klammernotation?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Object_basics#setting_object_members\">Wie erhält und setzt man die Methoden und Eigenschaften eines Objekts?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Object_basics#what_is_this\">Was ist <code>this</code> im Kontext eines Objekts?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript#object-oriented_programming_from_10000_meters\">Was ist objektorientierte Programmierung?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript#constructors_and_object_instances\">Was sind Konstruktoren und Instanzen, und wie erstellt man sie?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript#other_ways_to_create_object_instances\">Welche verschiedenen Möglichkeiten gibt es, Objekte in JavaScript zu erstellen?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"json","title":"JSON","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/JSON#json_structure\">Wie strukturiert man JSON-Daten und liest sie in JavaScript ein?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/JSON#loading_our_json\">Wie kann man eine JSON-Datei in eine Seite laden?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/JSON#converting_between_objects_and_text\">Wie konvertiert man ein JSON-Objekt in einen Textstring und zurück?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"events","title":"Events","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Events#event_handler_properties\">Was sind Event-Handler und wie benutzt man sie?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Events#inline_event_handlers_%e2%80%94_don%27t_use_these\">Was sind Inline-Event-Handler?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Events#using_addeventlistener\">Was macht die <code>addEventListener()</code>-Funktion und wie benutzt man sie?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Events#what_mechanism_should_i_use\">Welchen Mechanismus sollte ich verwenden, um Event-Code zu meinen Webseiten hinzuzufügen?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Events#event_objects\">Was sind Event-Objekte und wie verwendet man sie?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Events#preventing_default_behavior\">Wie verhindert man das standardmäßige Verhalten eines Events?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Event_bubbling\">Wie feuern Events auf verschachtelten Elementen ab? (Event-Propagation, auch zugehörig — Event-Bubbling und -Capturing)</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Event_bubbling#event_delegation\">Was ist Event-Delegation und wie funktioniert sie?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"objektorientiertes_javascript","title":"Objektorientiertes JavaScript","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes\">Was sind Objektprototypen?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes#the_constructor_property\">Was ist die constructor-Eigenschaft und wie kann man sie verwenden?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes#modifying_prototypes\">Wie fügt man Methoden zum Konstruktor hinzu?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript\">Wie erstellt man einen neuen Konstruktor, der seine Mitglieder von einem Eltern-Konstruktor erbt?</a></li>\n<li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript#object_member_summary\">Wann sollte man Vererbung in JavaScript verwenden?</a></li>\n</ul>"}},{"type":"prose","value":{"id":"web-apis","title":"Web-APIs","isH3":true,"content":"<ul>\n<li><a href=\"/de/docs/Learn_web_development/Core/Scripting/DOM_scripting#active_learning_basic_dom_manipulation\">Wie manipuliert man das DOM (z.B. Hinzufügen oder Entfernen von Elementen) mit JavaScript?</a></li>\n</ul>"}}],"isActive":true,"isMarkdown":true,"isTranslated":true,"locale":"de","mdn_url":"/de/docs/Learn_web_development/Howto/Solve_JavaScript_problems","modified":"2025-02-17T00:20:27.000Z","native":"Deutsch","noIndexing":false,"other_translations":[{"locale":"en-US","title":"Solve common JavaScript problems","native":"English (US)"},{"locale":"es","title":"Resuelva problemas comunes en su código JavaScript","native":"Español"},{"locale":"ja","title":"JavaScript のコードのよくある問題を解決する","native":"日本語"},{"locale":"ko","title":"Solve common problems in your JavaScript code","native":"한국어"},{"locale":"pt-BR","title":"Solve common problems in your JavaScript code","native":"Português (do Brasil)"},{"locale":"ru","title":"Решите общие проблемы в вашем JavaScript-коде","native":"Русский"},{"locale":"zh-CN","title":"解决 JavaSctript 代码的常见问题","native":"中文 (简体)"},{"locale":"zh-TW","title":"JavaScript 解決常見的問題","native":"正體中文 (繁體)"}],"pageTitle":"Häufige JavaScript-Probleme lösen - Lernen Sie Webentwicklung | MDN","parents":[{"uri":"/de/docs/Learn_web_development","title":"Lernen Sie Webentwicklung"},{"uri":"/de/docs/Learn_web_development/Howto","title":"Anleitung zur Lösung häufiger Probleme"},{"uri":"/de/docs/Learn_web_development/Howto/Solve_JavaScript_problems","title":"Häufige JavaScript-Probleme lösen"}],"popularity":null,"short_title":"Häufige JavaScript-Probleme lösen","sidebarHTML":"<ol><li class=\"section\"><a href=\"/de/docs/Learn_web_development/Getting_started\">Einstiegsmodule</a></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Getting_started/Environment_setup\">Umgebung einrichten</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Getting_started/Environment_setup/Installing_software\">Installation grundlegender Software</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Environment_setup/Browsing_the_web\">Surfen im Web</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Environment_setup/Code_editors\">Code-Editor</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Environment_setup/Dealing_with_files\">Umgang mit Dateien</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Environment_setup/Command_line\">Leitfaden für die Befehlszeilen-Einführung</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Getting_started/Your_first_website\">Ihre erste Website</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Getting_started/Your_first_website/What_will_your_website_look_like\">Wie wird Ihre Website aussehen?</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Your_first_website/Creating_the_content\">HTML: Erstellen der Inhalte</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Your_first_website/Styling_the_content\">CSS: Gestaltung des Inhalts</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Your_first_website/Adding_interactivity\">JavaScript: Interaktivität hinzufügen</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Your_first_website/Publishing_your_website\">Veröffentlichen Ihrer Website</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Getting_started/Web_standards\">Webstandards</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Getting_started/Web_standards/How_the_web_works\">How the web works</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Web_standards/The_web_standards_model\">Das Modell der Webstandards</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Web_standards/How_browsers_load_websites\">Wie Browser Websites laden</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Getting_started/Soft_skills\">Soziale Kompetenzen</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Getting_started/Soft_skills/Research_and_learning\">Forschung und Lernen</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Soft_skills/Collaboration_and_teamwork\">Zusammenarbeit und Teamarbeit</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Soft_skills/Workflows_and_processes\">Workflows und Prozesse</a></li><li><a href=\"/de/docs/Learn_web_development/Getting_started/Soft_skills/Job_interviews\">Erfolgreich in Vorstellungsgesprächen</a></li></ol></details></li><li class=\"section\"><a href=\"/de/docs/Learn_web_development/Core\">Kernmodule</a></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Core/Structuring_content\">Inhalte mit HTML strukturieren</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Basic_HTML_syntax\">Grundlegende HTML-Syntax</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Webpage_metadata\">Was befindet sich im Kopf? Metadaten einer Webseite</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Headings_and_paragraphs\">Überschriften und Absätze in HTML</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Emphasis_and_importance\">Hervorhebung und Wichtigkeit</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Lists\">Listen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Structuring_documents\">Strukturierung von Dokumenten</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Advanced_text_features\">Erweiterte Textfunktionen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Creating_links\">Erstellen von Links</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Marking_up_a_letter\">Herausforderung: Eine E-Mail korrekt auszeichnen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Structuring_a_page_of_content\">Herausforderung: Strukturierung einer Inhaltsseite</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/HTML_images\">HTML-Bilder</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/HTML_video_and_audio\">HTML video und audio</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Mozilla_splash_page\">Herausforderung: Mozilla Splash-Seite</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/HTML_table_basics\">Grundlagen von HTML-Tabellen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Table_accessibility\">Barrierefreiheit von HTML-Tabellen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Planet_data_table\">Herausforderung: Strukturierung einer Planeten-Datentabelle</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/HTML_forms\">Formulare und Schaltflächen in HTML</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Structuring_content/Debugging_HTML\">Debugging von HTML</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Core/Styling_basics\">Grundlagen des CSS-Stylings</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/What_is_CSS\">Was ist CSS?</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Getting_started\">Einstieg in CSS</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Styling_a_bio_page\">Herausforderung: Gestaltung einer Biografie-Seite</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Basic_selectors\">Grundlagen der CSS-Selektoren</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Attribute_selectors\">Attribut-Selektoren</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Pseudo_classes_and_elements\">Pseudoklassen und Pseudoelemente</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Combinators\">Kombinatoren</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Box_model\">Das Box-Modell</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Handling_conflicts\">Umgang mit Konflikten</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Values_and_units\">CSS-Werte und -Einheiten</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Sizing\">Größenbestimmung von Elementen in CSS</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Backgrounds_and_borders\">Hintergründe und Rahmen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Overflow\">Überlaufender Inhalt</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Images_media_forms\">Bilder, Medien und Formularelemente</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Tables\">Tabellen stylen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Debugging_CSS\">Debugging CSS</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Fundamental_CSS_comprehension\">Herausforderung: Grundlegendes CSS-Verständnis</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Fancy_letterheaded_paper\">Herausforderung: Erstellung eines ansprechenden Briefpapiers</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Styling_basics/Cool-looking_box\">Herausforderung: Eine cool aussehende Box</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Core/Text_styling\">CSS-Textgestaltung</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Core/Text_styling/Fundamentals\">Grundlegendes zur Text- und Schriftgestaltung</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Text_styling/Styling_lists\">Listen gestalten</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Text_styling/Styling_links\">Gestaltung von Links</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Text_styling/Web_fonts\">Webfonts</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Text_styling/Typesetting_a_homepage\">Herausforderung: Setzen einer Startseite für eine Gemeinschaftsschule</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Core/CSS_layout\">CSS-Layout</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Core/CSS_layout/Introduction\">Einführung in CSS-Layout</a></li><li><a href=\"/de/docs/Learn_web_development/Core/CSS_layout/Floats\">Floats</a></li><li><a href=\"/de/docs/Learn_web_development/Core/CSS_layout/Positioning\">Platzierung</a></li><li><a href=\"/de/docs/Learn_web_development/Core/CSS_layout/Flexbox\">Flexbox</a></li><li><a href=\"/de/docs/Learn_web_development/Core/CSS_layout/Grids\">CSS-Grid-Layout</a></li><li><a href=\"/de/docs/Learn_web_development/Core/CSS_layout/Responsive_Design\">Responsives Design</a></li><li><a href=\"/de/docs/Learn_web_development/Core/CSS_layout/Media_queries\">Grundlagen von Media Query</a></li><li><a href=\"/de/docs/Learn_web_development/Core/CSS_layout/Fundamental_Layout_Comprehension\">Herausforderung: Grundlegendes Verständnis von Layouts</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Core/Scripting\">Dynamisches Scripting mit JavaScript</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/What_is_JavaScript\">Was ist JavaScript?</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/A_first_splash\">Erster Einblick in JavaScript</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/What_went_wrong\">Was ist schiefgelaufen? JavaScript-Fehlerbehebung</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Variables\">Speichern der benötigten Informationen — Variablen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Math\">Grundlegende Mathematik in JavaScript – Zahlen und Operatoren</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Strings\">Umgang mit Text — Zeichenketten in JavaScript</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Useful_string_methods\">Nützliche String-Methoden</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Arrays\">Arrays</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Silly_story_generator\">Herausforderung: Blödsinnige Geschichtengenerator</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Conditionals\">Entscheidungen in Ihrem Code treffen — Konditionalen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Loops\">Code-Schleifen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Functions\">Funktionen — wiederverwendbare Codeblöcke</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Build_your_own_function\">Erstellen Sie Ihre eigene Funktion</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Return_values\">Funktionsrückgabewerte</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Events\">Einführung in Ereignisse</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Event_bubbling\">Ereignis-Bubbling</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Image_gallery\">Herausforderung: Bildergalerie</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Object_basics\">JavaScript-Objektgrundlagen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/DOM_scripting\">Einführung in DOM-Scripting</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Network_requests\">Netzwerkanfragen mit JavaScript</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/JSON\">Arbeiten mit JSON</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript\">Debugging JavaScript and handling errors</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Core/Frameworks_libraries\">JavaScript-Frameworks und -Bibliotheken</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Core/Frameworks_libraries/Introduction\">Einführung in client-seitige Frameworks</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Frameworks_libraries/Main_features\">Hauptmerkmale von Frameworks</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Frameworks_libraries/React_getting_started\">Erste Schritte mit React</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Frameworks_libraries/React_todo_list_beginning\">Beginn unserer React To-Do-Liste</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Frameworks_libraries/React_components\">Komponenten in unserer React-App erstellen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Frameworks_libraries/React_interactivity_events_state\">React Interaktivität: Events und State</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Frameworks_libraries/React_interactivity_filtering_conditional_rendering\">Reaktivität in React: Bearbeiten, Filtern, bedingtes Rendern</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Frameworks_libraries/React_accessibility\">Barrierefreiheit in React</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Frameworks_libraries/React_resources\">React-Ressourcen</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Core/Accessibility\">Barrierefreiheit</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Core/Accessibility/What_is_accessibility\">Was ist Barrierefreiheit?</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Accessibility/Tooling\">Barrierefreiheitstools und unterstützende Technologien</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Accessibility/HTML\">HTML: Eine gute Grundlage für Barrierefreiheit</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Accessibility/CSS_and_JavaScript\">CSS and JavaScript Zugänglichkeitsbest Practices</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Accessibility/WAI-ARIA_basics\">WAI-ARIA Grundlagen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Accessibility/Multimedia\">Barrierefreie Multimedia-Inhalte</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Accessibility/Mobile\">Mobile Accessibility</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Accessibility/Accessibility_troubleshooting\">Herausforderung: Barrierefreiheits-Fehlerbehebung</a></li></ol></details></li><li><a href=\"/de/docs/Learn_web_development/Core/Design_for_developers\">Design für Entwickler:innen</a></li><li><a href=\"/de/docs/Learn_web_development/Core/Version_control\">Versionskontrolle</a></li><li class=\"section\"><a href=\"/de/docs/Learn_web_development/Extensions\">Erweiterungsmodule</a></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects\">Advanced JavaScript objects</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes\">Objektprototypen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object-oriented_programming\">Objektorientierte Programmierung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript\">Klassen in JavaScript</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_building_practice\">Objektbaupraxis</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Adding_bouncing_balls_features\">Herausforderung: Hinzufügen von Funktionen zu unserem hüpfenden Ball-Demo</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_APIs\">Client-seitige Web-APIs</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_APIs/Introduction\">Einführung in Web-APIs</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_APIs/Video_and_audio_APIs\">Video- und Audio-APIs</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_APIs/Drawing_graphics\">Zeichnen von Grafiken</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_APIs/Client-side_storage\">Client-seitiger Speicher</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_APIs/Third_party_APIs\">Third-party APIs</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Async_JS\">Asynchrones JavaScript</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Extensions/Async_JS/Introducing\">Einführung in asynchrones JavaScript</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Async_JS/Promises\">Anleitung zur Verwendung von Promises</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Async_JS/Implementing_a_promise-based_API\">Wie man eine Promise-basierte API implementiert</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Async_JS/Introducing_workers\">Einführung in Worker</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Async_JS/Sequencing_animations\">Herausforderung: Animationen sequenzieren</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Forms\">Webformulare — Arbeiten mit Benutzerdaten</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Extensions/Forms/Your_first_form\">Ihr erstes Formular</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Forms/How_to_structure_a_web_form\">Wie man ein Webformular strukturiert</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Forms/Basic_native_form_controls\">Grundlegende native Formularsteuerungen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Forms/HTML5_input_types\">Die HTML5-Eingabetypen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Forms/Other_form_controls\">Andere Formularelemente</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Forms/Styling_web_forms\">Styling von Webformularen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Forms/Advanced_form_styling\">Fortgeschrittenes Formular-Styling</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Forms/UI_pseudo-classes\">UI-Pseudoklassen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Forms/Form_validation\">Client-seitige Formularvalidierung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Forms/Sending_and_retrieving_form_data\">Senden von Formulardaten</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_tools\">Verständnis für clientseitige Tools</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_tools/Overview\">Überblick über Client-seitige Tools</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_tools/Package_management\">Grundlagen des Paketmanagements</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_tools/Introducing_complete_toolchain\">Einführung in eine vollständige Werkzeugkette</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Client-side_tools/Deployment\">Bereitstellung unserer App</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Server-side\">Serverseitige Programmierung</a></summary><ol><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/First_steps\">Erste Schritte auf der Serverseite</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/First_steps/Introduction\">Einführung in die Server-Seite</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/First_steps/Client-Server_overview\">Überblick über Client-Server</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/First_steps/Web_frameworks\">Server-seitige Web-Frameworks</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/First_steps/Website_security\">Website-Sicherheit</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django\">Django Web-Framework (Python)</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Introduction\">Einführung in Django</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/development_environment\">Einrichten einer Django-Entwicklungsumgebung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Tutorial_local_library_website\">Django Tutorial: Die Website der lokalen Bibliothek</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/skeleton_website\">Django-Tutorial Teil 2: Erstellen einer Skelett-Website</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Models\">Django Tutorial Teil 3: Verwenden von Modellen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Admin_site\">Django Tutorial Teil 4: Die Django Admin-Seite</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Home_page\">Django Tutorial Teil 5: Erstellen unserer Homepage</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Generic_views\">Django Tutorial Teil 6: Generische Listen- und Detailansichten</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Sessions\">Django-Tutorial Teil 7: Sitzungs-Framework</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Authentication\">Django-Tutorial Teil 8: Benutzer-Authentifizierung und -Berechtigungen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Forms\">Django Tutorial Teil 9: Arbeiten mit Formularen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Testing\">Django Tutorial Teil 10: Testen einer Django-Webanwendung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/Deployment\">Django-Tutorial Teil 11: Bereitstellung von Django für die Produktion</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/web_application_security\">Django Webanwendungssicherheit</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Django/django_assessment_blog\">Bewertung: DIY Django Mini-Blog</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs\">Express Web-Framework (Node.js)</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Introduction\">Einführung in Express/Node</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/development_environment\">Einrichten einer Node-Entwicklungsumgebung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Tutorial_local_library_website\">Express Tutorial: Die Website der lokalen Bibliothek</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/skeleton_website\">Express-Tutorial Teil 2: Erstellen einer Skelett-Website</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/mongoose\">Express-Tutorial Teil 3: Verwendung einer Datenbank (mit Mongoose)</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/routes\">Express Tutorial Teil 4: Routen und Controller</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Displaying_data\">Express Tutorial Teil 5: Bibliotheksdaten anzeigen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/forms\">Express Tutorial Teil 6: Arbeiten mit Formularen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/deployment\">Express Tutorial Teil 7: Bereitstellung im Produktionsumfeld</a></li></ol></details></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Performance\">Web-Performance</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Extensions/Performance/why_web_performance\">Das \"Warum\" der Web-Performance</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Performance/What_is_web_performance\">Was ist Web-Performance?</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Performance/Perceived_performance\">Wahrgenommene Leistung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Performance/Measuring_performance\">Leistungsmessung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Performance/Multimedia\">Multimedia: Bilder</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Performance/video\">Multimedia: video</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Performance/JavaScript\">JavaScript-Leistungsoptimierung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Performance/HTML\">HTML-Performance-Optimierung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Performance/CSS\">CSS-Leistungsoptimierung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Performance/business_case_for_performance\">Der geschäftliche Nutzen der Web-Performance</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/de/docs/Learn_web_development/Extensions/Testing\">Tests</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Extensions/Testing/Introduction\">Einführung in das Cross-Browser-Testing</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Testing/Testing_strategies\">Strategien zur Durchführung von Tests</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Testing/HTML_and_CSS\">Umgang mit häufigen HTML- und CSS-Problemen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Testing/Feature_detection\">Implementierung der Funktionsprüfung</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Testing/Automated_testing\">Einführung in automatisiertes Testen</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Testing/Your_own_automation_environment\">Einrichtung Ihrer eigenen Testautomatisierungsumgebung</a></li></ol></details></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Transform_animate\">CSS transformieren und animieren</a></li><li><a href=\"/de/docs/Learn_web_development/Extensions/Security_privacy\">Sicherheit und Datenschutz</a></li><li class=\"section\">Weitere Ressourcen</li><li class=\"toggle\"><details open=\"\"><summary><a href=\"/de/docs/Learn_web_development/Howto\">Häufige Probleme lösen</a></summary><ol><li><a href=\"/de/docs/Learn_web_development/Howto/Solve_HTML_problems\">Häufige HTML-Probleme lösen</a></li><li><a href=\"/de/docs/Learn_web_development/Howto/Solve_CSS_problems\">Häufige CSS-Probleme lösen</a></li><li><em><a href=\"/de/docs/Learn_web_development/Howto/Solve_JavaScript_problems\" aria-current=\"page\">Häufige JavaScript-Probleme lösen</a></em></li><li><a href=\"/de/docs/Learn_web_development/Howto/Web_mechanics\">Webmechanik</a></li><li><a href=\"/de/docs/Learn_web_development/Howto/Tools_and_setup\">Tools und Einrichtung</a></li><li><a href=\"/de/docs/Learn_web_development/Howto/Design_and_accessibility\">Design und Barrierefreiheit</a></li></ol></details></li><li><a href=\"/de/docs/Learn_web_development/About\">Über</a></li><li><a href=\"/de/docs/Learn_web_development/Educators\">Ressourcen für Lehrkräfte</a></li><li><a href=\"/de/docs/Learn_web_development/Changelog\">Änderungsprotokoll</a></li></ol>","source":{"folder":"de/learn_web_development/howto/solve_javascript_problems","github_url":"https://github.com/mdn/translated-content-de/blob/main/files/de/learn_web_development/howto/solve_javascript_problems/index.md","last_commit_url":"https://github.com/mdn/translated-content-de/commit/452fe502cfb4c9a91c346af17370ecfb6a8bd17e","filename":"index.md"},"summary":"Die folgenden Links verweisen auf Lösungen für häufige Probleme, die bei der Programmierung mit JavaScript auftreten können.","title":"Häufige JavaScript-Probleme lösen","toc":[{"text":"Häufige Anfängerfehler","id":"häufige_anfängerfehler"},{"text":"Grundlegende Definitionen","id":"grundlegende_definitionen"},{"text":"Grundlegende Anwendungsfälle","id":"grundlegende_anwendungsfälle"},{"text":"Mittelstufe Anwendungsfälle","id":"mittelstufe_anwendungsfälle"}],"pageType":"landing-page"}}</script></body></html>