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(简体)</span></a></li></ul></div></div></li></ul></div></div></div></div><div class="main-wrapper"><div class="sidebar-container"><aside id="sidebar-quicklinks" class="sidebar" data-macro="APIRef"><button type="button" class="button action backdrop" aria-label="Collapse sidebar"><span class="button-wrap"></span></button><nav aria-label="Related Topics" class="sidebar-inner"><header class="sidebar-actions"><section class="sidebar-filter-container"><div class="sidebar-filter "><label id="sidebar-filter-label" class="sidebar-filter-label" for="sidebar-filter-input"><span class="icon icon-filter"></span><span class="visually-hidden">Filter sidebar</span></label><input id="sidebar-filter-input" autoComplete="off" class="sidebar-filter-input-field false" type="text" placeholder="Filter" value=""/><button type="button" class="button action has-icon clear-sidebar-filter-button"><span class="button-wrap"><span class="icon icon-cancel "></span><span class="visually-hidden">Clear filter input</span></span></button></div></section></header><div class="sidebar-inner-nav"><div class="in-nav-toc"><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#instance_properties">Instance properties</a></li><li class="document-toc-item "><a class="document-toc-link" href="#instance_methods">Instance methods</a></li><li class="document-toc-item "><a class="document-toc-link" href="#events">Events</a></li><li class="document-toc-item "><a class="document-toc-link" href="#examples">Examples</a></li><li class="document-toc-item "><a class="document-toc-link" href="#specifications">Specifications</a></li><li class="document-toc-item "><a class="document-toc-link" href="#browser_compatibility">Browser compatibility</a></li><li class="document-toc-item "><a class="document-toc-link" href="#see_also">See also</a></li></ul></section></div></div><div class="sidebar-body"><ol><li class="section"><a href="/en-US/docs/Web/API/Service_Worker_API">Service Worker API</a></li><li class="section"><em><a href="/en-US/docs/Web/API/ServiceWorker" aria-current="page"><code>ServiceWorker</code></a></em></li><li class="toggle"><details open=""><summary>Instance properties</summary><ol><li><a href="/en-US/docs/Web/API/ServiceWorker/scriptURL"><code>scriptURL</code></a></li><li><a href="/en-US/docs/Web/API/ServiceWorker/state"><code>state</code></a></li></ol></details></li><li class="toggle"><details open=""><summary>Instance methods</summary><ol><li><a href="/en-US/docs/Web/API/ServiceWorker/postMessage"><code>postMessage()</code></a></li></ol></details></li><li class="toggle"><details open=""><summary>Events</summary><ol><li><a href="/en-US/docs/Web/API/ServiceWorker/error_event"><code>error</code></a></li><li><a href="/en-US/docs/Web/API/ServiceWorker/statechange_event"><code>statechange</code></a></li></ol></details></li><li class="toggle"><details open=""><summary>Inheritance</summary><ol><li><a href="/en-US/docs/Web/API/EventTarget"><code>EventTarget</code></a></li></ol></details></li><li class="toggle"><details open=""><summary>Related pages for Service Workers API</summary><ol><li><a href="/en-US/docs/Web/API/Cache"><code>Cache</code></a></li><li><a href="/en-US/docs/Web/API/CacheStorage"><code>CacheStorage</code></a></li><li><a href="/en-US/docs/Web/API/Client"><code>Client</code></a></li><li><a href="/en-US/docs/Web/API/Clients"><code>Clients</code></a></li><li><a href="/en-US/docs/Web/API/ExtendableEvent"><code>ExtendableEvent</code></a></li><li><a href="/en-US/docs/Web/API/ExtendableMessageEvent"><code>ExtendableMessageEvent</code></a></li><li><a href="/en-US/docs/Web/API/FetchEvent"><code>FetchEvent</code></a></li><li><a href="/en-US/docs/Web/API/InstallEvent"><code>InstallEvent</code></a></li><li><a href="/en-US/docs/Web/API/NavigationPreloadManager"><code>NavigationPreloadManager</code></a></li><li><a href="/en-US/docs/Web/API/Navigator/serviceWorker"><code>Navigator.serviceWorker</code></a></li><li><a href="/en-US/docs/Web/API/ServiceWorkerContainer"><code>ServiceWorkerContainer</code></a></li><li><a href="/en-US/docs/Web/API/ServiceWorkerGlobalScope"><code>ServiceWorkerGlobalScope</code></a></li><li><a href="/en-US/docs/Web/API/ServiceWorkerRegistration"><code>ServiceWorkerRegistration</code></a></li><li><a href="/en-US/docs/Web/API/Window/caches"><code>Window.caches</code></a></li><li><a href="/en-US/docs/Web/API/WindowClient"><code>WindowClient</code></a></li><li><a href="/en-US/docs/Web/API/WorkerGlobalScope/caches"><code>WorkerGlobalScope.caches</code></a></li><li><a href="/en-US/docs/Web/API/WorkerNavigator/serviceWorker"><code>WorkerNavigator.serviceWorker</code></a></li></ol></details></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 this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#instance_properties">Instance properties</a></li><li class="document-toc-item "><a class="document-toc-link" href="#instance_methods">Instance methods</a></li><li class="document-toc-item "><a class="document-toc-link" href="#events">Events</a></li><li class="document-toc-item "><a class="document-toc-link" href="#examples">Examples</a></li><li class="document-toc-item "><a class="document-toc-link" href="#specifications">Specifications</a></li><li class="document-toc-item "><a class="document-toc-link" href="#browser_compatibility">Browser compatibility</a></li><li class="document-toc-item "><a class="document-toc-link" href="#see_also">See also</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="en-US"><header><h1>ServiceWorker</h1></header><div class="section-content"><div class="notecard secure"><p><strong>Secure context:</strong> This feature is available only in <a href="/en-US/docs/Web/Security/Secure_Contexts">secure contexts</a> (HTTPS), in some or all <a href="#browser_compatibility">supporting browsers</a>.</p></div><div class="notecard note"> <p><strong>Note:</strong> This feature is available in <a href="/en-US/docs/Web/API/Web_Workers_API">Web Workers</a>.</p> </div> <p>The <strong><code>ServiceWorker</code></strong> interface of the <a href="/en-US/docs/Web/API/Service_Worker_API">Service Worker API</a> provides a reference to a service worker. Multiple <a href="/en-US/docs/Glossary/Browsing_context">browsing contexts</a> (e.g. pages, workers, etc.) can be associated with the same service worker, each through a unique <code>ServiceWorker</code> object.</p> <p>A <code>ServiceWorker</code> object is available via a number of properties:</p> <ul> <li><a href="/en-US/docs/Web/API/ServiceWorkerRegistration/active"><code>ServiceWorkerRegistration.active</code></a></li> <li><a href="/en-US/docs/Web/API/ServiceWorkerGlobalScope/serviceWorker"><code>ServiceWorkerGlobalScope.serviceWorker</code></a></li> <li><a href="/en-US/docs/Web/API/ServiceWorkerContainer/controller"><code>ServiceWorkerContainer.controller</code></a> — when the service worker is in <code>activating</code> or <code>activated</code> state</li> <li><a href="/en-US/docs/Web/API/ServiceWorkerRegistration/installing"><code>ServiceWorkerRegistration.installing</code></a> — when the service worker is in <code>installing</code> state</li> <li><a href="/en-US/docs/Web/API/ServiceWorkerRegistration/waiting"><code>ServiceWorkerRegistration.waiting</code></a> — when the service worker is in <code>installed</code> state</li> </ul> <p> The <a href="/en-US/docs/Web/API/ServiceWorker/state"><code>ServiceWorker.state</code></a> property and <a href="/en-US/docs/Web/API/ServiceWorker/statechange_event"><code>statechanged</code> event</a> can be used to check and observe changes in the lifecycle-state of the object's associated service worker. Related lifecycle events, such as <a href="/en-US/docs/Web/API/ServiceWorkerGlobalScope/install_event"><code>install</code></a> and <a href="/en-US/docs/Web/API/ServiceWorkerGlobalScope/activate_event"><code>activate</code></a> are fired at the service worker itself. </p> <p> Service workers allow static import of <a href="/en-US/docs/Web/JavaScript/Guide/Modules">ECMAScript modules</a>, if supported, using <a href="/en-US/docs/Web/JavaScript/Reference/Statements/import"><code>import</code></a>. Dynamic import is disallowed by the specification — calling <a href="/en-US/docs/Web/JavaScript/Reference/Operators/import"><code>import()</code></a> will throw. </p> <p> Service workers can only be registered in the Window scope in some or all browsers, because the <code>ServiceWorker</code> object is not exposed to <a href="/en-US/docs/Web/API/DedicatedWorkerGlobalScope"><code>DedicatedWorkerGlobalScope</code></a> and <a href="/en-US/docs/Web/API/SharedWorkerGlobalScope"><code>SharedWorkerGlobalScope</code></a>. Check the <a href="#browser_compatibility">browser compatibility</a> for information. </p><svg viewBox="-1 -1 650 42" preserveAspectRatio="xMinYMin meet"> <a style="text-decoration: none;" href="/en-US/docs/Web/API/EventTarget"> <rect x="0" y="0" width="88" height="25" fill="#fff" stroke="#D4DDE4" stroke-width="2px"></rect> <text x="44" y="16" font-size="10px" fill="#4D4E53" text-anchor="middle"> EventTarget </text> </a> <line x1="88" y1="14" x2="118" y2="14" stroke="#D4DDE4"></line> <polyline points="88,14 98,9 98,19 88,14" stroke="#D4DDE4" fill="#fff"></polyline> <a style="text-decoration: none;" href="/en-US/docs/Web/API/ServiceWorker" aria-current="page"> <rect x="118" y="0" width="104" height="25" fill="#F4F7F8" stroke="#D4DDE4" stroke-width="2px"></rect> <text x="170" y="16" font-size="10px" fill="#4D4E53" text-anchor="middle"> ServiceWorker </text> </a></svg></div><section aria-labelledby="instance_properties"><h2 id="instance_properties"><a href="#instance_properties">Instance properties</a></h2><div class="section-content"><p><em>The <code>ServiceWorker</code> interface inherits properties from its parent, <a href="/en-US/docs/Web/API/EventTarget"><code>EventTarget</code></a>.</em></p> <dl> <dt id="serviceworker.scripturl"><a href="/en-US/docs/Web/API/ServiceWorker/scriptURL"><code>ServiceWorker.scriptURL</code></a> <span class="badge inline readonly" title="This value may not be changed.">Read only </span></dt> <dd> <p>Returns the <code>ServiceWorker</code> serialized script URL defined as part of <a href="/en-US/docs/Web/API/ServiceWorkerRegistration"><code>ServiceWorkerRegistration</code></a>. The URL must be on the same origin as the document that registers the <code>ServiceWorker</code>.</p> </dd> <dt id="serviceworker.state"><a href="/en-US/docs/Web/API/ServiceWorker/state"><code>ServiceWorker.state</code></a> <span class="badge inline readonly" title="This value may not be changed.">Read only </span></dt> <dd> <p>Returns the state of the service worker. It returns one of the following values: <code>parsed</code>, <code>installing</code>, <code>installed</code>, <code>activating</code>, <code>activated</code>, or <code>redundant</code>.</p> </dd> </dl></div></section><section aria-labelledby="instance_methods"><h2 id="instance_methods"><a href="#instance_methods">Instance methods</a></h2><div class="section-content"><p><em>The <code>ServiceWorker</code> interface inherits methods from its parent, <a href="/en-US/docs/Web/API/EventTarget"><code>EventTarget</code></a>.</em></p> <dl> <dt id="serviceworker.postmessage"><a href="/en-US/docs/Web/API/ServiceWorker/postMessage"><code>ServiceWorker.postMessage()</code></a></dt> <dd> <p>Sends a message — consisting of any <a href="/en-US/docs/Web/API/Web_Workers_API/Structured_clone_algorithm">structured-cloneable</a> JavaScript object — to the service worker. The message is transmitted to the service worker using a <a href="/en-US/docs/Web/API/ServiceWorkerGlobalScope/message_event" title="message"><code>message</code></a> event on its global scope.</p> </dd> </dl></div></section><section aria-labelledby="events"><h2 id="events"><a href="#events">Events</a></h2><div class="section-content"><dl> <dt id="statechange"><a href="/en-US/docs/Web/API/ServiceWorker/statechange_event" title="statechange"><code>statechange</code></a></dt> <dd> <p>Fired when <a href="/en-US/docs/Web/API/ServiceWorker/state"><code>ServiceWorker.state</code></a> changes.</p> </dd> <dt id="error"><a href="/en-US/docs/Web/API/ServiceWorker/error_event" title="error"><code>error</code></a></dt> <dd> <p>Fired when an error happens inside the <code>ServiceWorker</code> object.</p> </dd> </dl></div></section><section aria-labelledby="examples"><h2 id="examples"><a href="#examples">Examples</a></h2><div class="section-content"><p>This code snippet is from the <a href="https://github.com/GoogleChrome/samples/blob/gh-pages/service-worker/registration-events/index.html" class="external" target="_blank">service worker registration-events sample</a> (<a href="https://googlechrome.github.io/samples/service-worker/registration-events/" class="external" target="_blank">live demo</a>). The code listens for any change in the <a href="/en-US/docs/Web/API/ServiceWorker/state"><code>ServiceWorker.state</code></a> and returns its value.</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>if ("serviceWorker" in navigator) { navigator.serviceWorker .register("service-worker.js", { scope: "./", }) .then((registration) => { let serviceWorker; if (registration.installing) { serviceWorker = registration.installing; document.querySelector("#kind").textContent = "installing"; } else if (registration.waiting) { serviceWorker = registration.waiting; document.querySelector("#kind").textContent = "waiting"; } else if (registration.active) { serviceWorker = registration.active; document.querySelector("#kind").textContent = "active"; } if (serviceWorker) { // logState(serviceWorker.state); serviceWorker.addEventListener("statechange", (e) => { // logState(e.target.state); }); } }) .catch((error) => { // Something went wrong during registration. The service-worker.js file // might be unavailable or contain a syntax error. }); } else { // The current browser doesn't support service workers. // Perhaps it is too old or we are not in a Secure Context. } </code></pre></div></div></section><h2 id="specifications"><a href="#specifications">Specifications</a></h2><table class="standard-table"><thead><tr><th scope="col">Specification</th></tr></thead><tbody><tr><td><a href="https://w3c.github.io/ServiceWorker/#serviceworker-interface">Service Workers <br/><small># serviceworker-interface</small></a></td></tr></tbody></table><h2 id="browser_compatibility"><a href="#browser_compatibility">Browser compatibility</a></h2><p>BCD tables only load in the browser<noscript> with JavaScript enabled. Enable JavaScript to view data.</noscript></p><section aria-labelledby="see_also"><h2 id="see_also"><a href="#see_also">See also</a></h2><div class="section-content"><ul> <li><a href="https://web.dev/articles/offline-cookbook" class="external" target="_blank">The Offline Cookbook</a> (service workers)</li> <li><a href="/en-US/docs/Web/API/Service_Worker_API/Using_Service_Workers">Using Service Workers</a></li> <li><a href="https://github.com/mdn/dom-examples/tree/main/service-worker/simple-service-worker" class="external" target="_blank">Service worker basic code example</a></li> <li><a href="/en-US/docs/Web/API/Web_Workers_API/Using_web_workers">Using web workers</a></li> </ul></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg xmlns="http://www.w3.org/2000/svg" width="162" height="162" viewBox="0 0 162 162" fill="none" role="none"><mask id="b" fill="#fff"><path d="M97.203 47.04c8.113-7.886 18.004-13.871 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href="https://foundation.mozilla.org/">Mozilla Foundation</a>.<br/>Portions of this content are ©1998–2024 by individual mozilla.org contributors. Content available under <a href="/en-US/docs/MDN/Writing_guidelines/Attrib_copyright_license">a Creative Commons license</a>.</p></div></div></footer></div><script type="application/json" id="hydration">{"url":"/en-US/docs/Web/API/ServiceWorker","doc":{"isMarkdown":true,"isTranslated":false,"isActive":true,"flaws":{},"title":"ServiceWorker","mdn_url":"/en-US/docs/Web/API/ServiceWorker","locale":"en-US","native":"English (US)","browserCompat":["api.ServiceWorker"],"sidebarHTML":"<ol><li class=\"section\"><a href=\"/en-US/docs/Web/API/Service_Worker_API\">Service Worker API</a></li><li class=\"section\"><em><a href=\"/en-US/docs/Web/API/ServiceWorker\" aria-current=\"page\"><code>ServiceWorker</code></a></em></li><li class=\"toggle\"><details open=\"\"><summary>Instance properties</summary><ol><li><a href=\"/en-US/docs/Web/API/ServiceWorker/scriptURL\"><code>scriptURL</code></a></li><li><a href=\"/en-US/docs/Web/API/ServiceWorker/state\"><code>state</code></a></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary>Instance methods</summary><ol><li><a href=\"/en-US/docs/Web/API/ServiceWorker/postMessage\"><code>postMessage()</code></a></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary>Events</summary><ol><li><a href=\"/en-US/docs/Web/API/ServiceWorker/error_event\"><code>error</code></a></li><li><a href=\"/en-US/docs/Web/API/ServiceWorker/statechange_event\"><code>statechange</code></a></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary>Inheritance</summary><ol><li><a href=\"/en-US/docs/Web/API/EventTarget\"><code>EventTarget</code></a></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary>Related pages for Service Workers API</summary><ol><li><a href=\"/en-US/docs/Web/API/Cache\"><code>Cache</code></a></li><li><a href=\"/en-US/docs/Web/API/CacheStorage\"><code>CacheStorage</code></a></li><li><a href=\"/en-US/docs/Web/API/Client\"><code>Client</code></a></li><li><a href=\"/en-US/docs/Web/API/Clients\"><code>Clients</code></a></li><li><a href=\"/en-US/docs/Web/API/ExtendableEvent\"><code>ExtendableEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/ExtendableMessageEvent\"><code>ExtendableMessageEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/FetchEvent\"><code>FetchEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/InstallEvent\"><code>InstallEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/NavigationPreloadManager\"><code>NavigationPreloadManager</code></a></li><li><a href=\"/en-US/docs/Web/API/Navigator/serviceWorker\"><code>Navigator.serviceWorker</code></a></li><li><a href=\"/en-US/docs/Web/API/ServiceWorkerContainer\"><code>ServiceWorkerContainer</code></a></li><li><a href=\"/en-US/docs/Web/API/ServiceWorkerGlobalScope\"><code>ServiceWorkerGlobalScope</code></a></li><li><a href=\"/en-US/docs/Web/API/ServiceWorkerRegistration\"><code>ServiceWorkerRegistration</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/caches\"><code>Window.caches</code></a></li><li><a href=\"/en-US/docs/Web/API/WindowClient\"><code>WindowClient</code></a></li><li><a href=\"/en-US/docs/Web/API/WorkerGlobalScope/caches\"><code>WorkerGlobalScope.caches</code></a></li><li><a href=\"/en-US/docs/Web/API/WorkerNavigator/serviceWorker\"><code>WorkerNavigator.serviceWorker</code></a></li></ol></details></li></ol>","sidebarMacro":"APIRef","body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<div class=\"notecard secure\"><p><strong>Secure context:</strong> This feature is available only in <a href=\"/en-US/docs/Web/Security/Secure_Contexts\">secure contexts</a> (HTTPS), in some or all <a href=\"#browser_compatibility\">supporting browsers</a>.</p></div><div class=\"notecard note\">\n <p><strong>Note:</strong> This feature is available in <a href=\"/en-US/docs/Web/API/Web_Workers_API\">Web Workers</a>.</p>\n</div>\n<p>The <strong><code>ServiceWorker</code></strong> interface of the <a href=\"/en-US/docs/Web/API/Service_Worker_API\">Service Worker API</a> provides a reference to a service worker. Multiple <a href=\"/en-US/docs/Glossary/Browsing_context\">browsing contexts</a> (e.g. pages, workers, etc.) can be associated with the same service worker, each through a unique <code>ServiceWorker</code> object.</p>\n<p>A <code>ServiceWorker</code> object is available via a number of properties:</p>\n<ul>\n <li><a href=\"/en-US/docs/Web/API/ServiceWorkerRegistration/active\"><code>ServiceWorkerRegistration.active</code></a></li>\n <li><a href=\"/en-US/docs/Web/API/ServiceWorkerGlobalScope/serviceWorker\"><code>ServiceWorkerGlobalScope.serviceWorker</code></a></li>\n <li><a href=\"/en-US/docs/Web/API/ServiceWorkerContainer/controller\"><code>ServiceWorkerContainer.controller</code></a> — when the service worker is in <code>activating</code> or <code>activated</code> state</li>\n <li><a href=\"/en-US/docs/Web/API/ServiceWorkerRegistration/installing\"><code>ServiceWorkerRegistration.installing</code></a> — when the service worker is in <code>installing</code> state</li>\n <li><a href=\"/en-US/docs/Web/API/ServiceWorkerRegistration/waiting\"><code>ServiceWorkerRegistration.waiting</code></a> — when the service worker is in <code>installed</code> state</li>\n</ul>\n<p>\n The <a href=\"/en-US/docs/Web/API/ServiceWorker/state\"><code>ServiceWorker.state</code></a> property and <a href=\"/en-US/docs/Web/API/ServiceWorker/statechange_event\"><code>statechanged</code> event</a> can be used to check and observe changes in the lifecycle-state of the object's associated service worker.\n Related lifecycle events, such as <a href=\"/en-US/docs/Web/API/ServiceWorkerGlobalScope/install_event\"><code>install</code></a> and <a href=\"/en-US/docs/Web/API/ServiceWorkerGlobalScope/activate_event\"><code>activate</code></a> are fired at the service worker itself.\n</p>\n<p>\n Service workers allow static import of <a href=\"/en-US/docs/Web/JavaScript/Guide/Modules\">ECMAScript modules</a>, if supported, using <a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/import\"><code>import</code></a>.\n Dynamic import is disallowed by the specification — calling <a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/import\"><code>import()</code></a> will throw.\n</p>\n<p>\n Service workers can only be registered in the Window scope in some or all browsers, because the <code>ServiceWorker</code> object is not exposed to <a href=\"/en-US/docs/Web/API/DedicatedWorkerGlobalScope\"><code>DedicatedWorkerGlobalScope</code></a> and <a href=\"/en-US/docs/Web/API/SharedWorkerGlobalScope\"><code>SharedWorkerGlobalScope</code></a>.\n Check the <a href=\"#browser_compatibility\">browser compatibility</a> for information.\n</p><svg viewBox=\"-1 -1 650 42\" preserveAspectRatio=\"xMinYMin meet\">\n <a style=\"text-decoration: none;\" href=\"/en-US/docs/Web/API/EventTarget\">\n <rect x=\"0\" y=\"0\" width=\"88\" height=\"25\" fill=\"#fff\" stroke=\"#D4DDE4\" stroke-width=\"2px\"></rect>\n <text x=\"44\" y=\"16\" font-size=\"10px\" fill=\"#4D4E53\" text-anchor=\"middle\">\n EventTarget\n </text>\n </a>\n <line x1=\"88\" y1=\"14\" x2=\"118\" y2=\"14\" stroke=\"#D4DDE4\"></line>\n <polyline points=\"88,14 98,9 98,19 88,14\" stroke=\"#D4DDE4\" fill=\"#fff\"></polyline>\n <a style=\"text-decoration: none;\" href=\"/en-US/docs/Web/API/ServiceWorker\" aria-current=\"page\">\n <rect x=\"118\" y=\"0\" width=\"104\" height=\"25\" fill=\"#F4F7F8\" stroke=\"#D4DDE4\" stroke-width=\"2px\"></rect>\n <text x=\"170\" y=\"16\" font-size=\"10px\" fill=\"#4D4E53\" text-anchor=\"middle\">\n ServiceWorker\n </text>\n </a></svg>"}},{"type":"prose","value":{"id":"instance_properties","title":"Instance properties","isH3":false,"content":"<p><em>The <code>ServiceWorker</code> interface inherits properties from its parent, <a href=\"/en-US/docs/Web/API/EventTarget\"><code>EventTarget</code></a>.</em></p>\n<dl>\n <dt id=\"serviceworker.scripturl\"><a href=\"/en-US/docs/Web/API/ServiceWorker/scriptURL\"><code>ServiceWorker.scriptURL</code></a> <span class=\"badge inline readonly\" title=\"This value may not be changed.\">Read only </span></dt>\n <dd>\n <p>Returns the <code>ServiceWorker</code> serialized script URL defined as part of <a href=\"/en-US/docs/Web/API/ServiceWorkerRegistration\"><code>ServiceWorkerRegistration</code></a>. The URL must be on the same origin as the document that registers the <code>ServiceWorker</code>.</p>\n </dd>\n <dt id=\"serviceworker.state\"><a href=\"/en-US/docs/Web/API/ServiceWorker/state\"><code>ServiceWorker.state</code></a> <span class=\"badge inline readonly\" title=\"This value may not be changed.\">Read only </span></dt>\n <dd>\n <p>Returns the state of the service worker. It returns one of the following values: <code>parsed</code>, <code>installing</code>, <code>installed</code>, <code>activating</code>, <code>activated</code>, or <code>redundant</code>.</p>\n </dd>\n</dl>"}},{"type":"prose","value":{"id":"instance_methods","title":"Instance methods","isH3":false,"content":"<p><em>The <code>ServiceWorker</code> interface inherits methods from its parent, <a href=\"/en-US/docs/Web/API/EventTarget\"><code>EventTarget</code></a>.</em></p>\n<dl>\n <dt id=\"serviceworker.postmessage\"><a href=\"/en-US/docs/Web/API/ServiceWorker/postMessage\"><code>ServiceWorker.postMessage()</code></a></dt>\n <dd>\n <p>Sends a message — consisting of any <a href=\"/en-US/docs/Web/API/Web_Workers_API/Structured_clone_algorithm\">structured-cloneable</a> JavaScript object — to the service worker. The message is transmitted to the service worker using a <a href=\"/en-US/docs/Web/API/ServiceWorkerGlobalScope/message_event\" title=\"message\"><code>message</code></a> event on its global scope.</p>\n </dd>\n</dl>"}},{"type":"prose","value":{"id":"events","title":"Events","isH3":false,"content":"<dl>\n <dt id=\"statechange\"><a href=\"/en-US/docs/Web/API/ServiceWorker/statechange_event\" title=\"statechange\"><code>statechange</code></a></dt>\n <dd>\n <p>Fired when <a href=\"/en-US/docs/Web/API/ServiceWorker/state\"><code>ServiceWorker.state</code></a> changes.</p>\n </dd>\n <dt id=\"error\"><a href=\"/en-US/docs/Web/API/ServiceWorker/error_event\" title=\"error\"><code>error</code></a></dt>\n <dd>\n <p>Fired when an error happens inside the <code>ServiceWorker</code> object.</p>\n </dd>\n</dl>"}},{"type":"prose","value":{"id":"examples","title":"Examples","isH3":false,"content":"<p>This code snippet is from the <a href=\"https://github.com/GoogleChrome/samples/blob/gh-pages/service-worker/registration-events/index.html\" class=\"external\" target=\"_blank\">service worker registration-events sample</a> (<a href=\"https://googlechrome.github.io/samples/service-worker/registration-events/\" class=\"external\" target=\"_blank\">live demo</a>). The code listens for any change in the <a href=\"/en-US/docs/Web/API/ServiceWorker/state\"><code>ServiceWorker.state</code></a> and returns its value.</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>if (\"serviceWorker\" in navigator) {\n navigator.serviceWorker\n .register(\"service-worker.js\", {\n scope: \"./\",\n })\n .then((registration) => {\n let serviceWorker;\n if (registration.installing) {\n serviceWorker = registration.installing;\n document.querySelector(\"#kind\").textContent = \"installing\";\n } else if (registration.waiting) {\n serviceWorker = registration.waiting;\n document.querySelector(\"#kind\").textContent = \"waiting\";\n } else if (registration.active) {\n serviceWorker = registration.active;\n document.querySelector(\"#kind\").textContent = \"active\";\n }\n if (serviceWorker) {\n // logState(serviceWorker.state);\n serviceWorker.addEventListener(\"statechange\", (e) => {\n // logState(e.target.state);\n });\n }\n })\n .catch((error) => {\n // Something went wrong during registration. The service-worker.js file\n // might be unavailable or contain a syntax error.\n });\n} else {\n // The current browser doesn't support service workers.\n // Perhaps it is too old or we are not in a Secure Context.\n}\n</code></pre></div>"}},{"type":"specifications","value":{"title":"Specifications","id":"specifications","isH3":false,"specifications":[{"bcdSpecificationURL":"https://w3c.github.io/ServiceWorker/#serviceworker-interface","title":"Service Workers"}],"query":"api.ServiceWorker"}},{"type":"browser_compatibility","value":{"title":"Browser compatibility","id":"browser_compatibility","isH3":false,"query":"api.ServiceWorker"}},{"type":"prose","value":{"id":"see_also","title":"See also","isH3":false,"content":"<ul>\n <li><a href=\"https://web.dev/articles/offline-cookbook\" class=\"external\" target=\"_blank\">The Offline Cookbook</a> (service workers)</li>\n <li><a href=\"/en-US/docs/Web/API/Service_Worker_API/Using_Service_Workers\">Using Service Workers</a></li>\n <li><a href=\"https://github.com/mdn/dom-examples/tree/main/service-worker/simple-service-worker\" class=\"external\" target=\"_blank\">Service worker basic code example</a></li>\n <li><a href=\"/en-US/docs/Web/API/Web_Workers_API/Using_web_workers\">Using web workers</a></li>\n</ul>"}}],"toc":[{"text":"Instance properties","id":"instance_properties"},{"text":"Instance methods","id":"instance_methods"},{"text":"Events","id":"events"},{"text":"Examples","id":"examples"},{"text":"Specifications","id":"specifications"},{"text":"Browser compatibility","id":"browser_compatibility"},{"text":"See also","id":"see_also"}],"summary":"The ServiceWorker interface of the Service Worker API provides a reference to a service worker. Multiple browsing contexts (e.g. pages, workers, etc.) can be associated with the same service worker, each through a unique ServiceWorker object.","popularity":0,"modified":"2024-11-22T03:34:08.000Z","other_translations":[{"locale":"de","title":"ServiceWorker","native":"Deutsch"},{"locale":"fr","title":"ServiceWorker","native":"Français"},{"locale":"ja","title":"ServiceWorker","native":"日本語"},{"locale":"ko","title":"ServiceWorker","native":"한국어"},{"locale":"ru","title":"ServiceWorker","native":"Русский"},{"locale":"zh-CN","title":"ServiceWorker","native":"中文 (简体)"}],"pageType":"web-api-interface","source":{"folder":"en-us/web/api/serviceworker","github_url":"https://github.com/mdn/content/blob/main/files/en-us/web/api/serviceworker/index.md","last_commit_url":"https://github.com/mdn/content/commit/5d29bef0815f8cc4b5b152b9ee1ab53f002ee617","filename":"index.md"},"short_title":"ServiceWorker","parents":[{"uri":"/en-US/docs/Web","title":"References"},{"uri":"/en-US/docs/Web/API","title":"Web APIs"},{"uri":"/en-US/docs/Web/API/ServiceWorker","title":"ServiceWorker"}],"pageTitle":"ServiceWorker - Web APIs | MDN","noIndexing":false}}</script></body></html>