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diff --git a/files/zh-cn/web/api/fetchobserver/index.html b/files/zh-cn/web/api/fetchobserver/index.html deleted file mode 100644 index 9bd7699388..0000000000 --- a/files/zh-cn/web/api/fetchobserver/index.html +++ /dev/null @@ -1,145 +0,0 @@ ---- -title: FetchObserver -slug: Web/API/FetchObserver -translation_of: Web/API/FetchObserver ---- -<div>{{draft}}{{APIRef("Fetch API")}}{{SeeCompatTable}}</div> - -<p><font><font>在</font></font><strong><code>FetchObserver</code></strong><font><font>接口</font></font><a href="https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API"><font><font>提取API</font></font></a><font><font>表示观察者对象,它允许您检索关于为获取请求的状态信息。</font></font></p> - -<h2 id="Properties">Properties</h2> - -<p><em><font><font>FetchObserver接口从其父接口继承属性</font></font><a href="https://developer.mozilla.org/en-US/docs/Web/API/EventTarget" title="EventTarget是一个由可以接收事件的对象实现的接口,并且可以为它们提供监听器。"><code>EventTarget</code></a><font><font>。</font></font></em></p> - -<dl> - <dt>{{domxref("FetchObserver.state")}} {{readonlyInline}}</dt> - <dd>Returns a <code>FetchState</code> enum value indicating the current state of the fetch request.</dd> -</dl> - -<h3 id="Event_handlers">Event handlers</h3> - -<dl> - <dt>{{domxref("FetchObserver.onstatechange")}}</dt> - <dd>Invoked when a {{event("statechange_(cancellable_fetch)", "statechange")}} event fires, i.e. when the state of the fetch request changes.</dd> - <dt>{{domxref("FetchObserver.onrequestprogress")}}</dt> - <dd>Invoked when a {{event("requestprogress")}} event fires, i.e. when the request progresses.</dd> - <dt>{{domxref("FetchObserver.onresponseprogress")}}</dt> - <dd>Invoked when a {{event("responseprogress")}} event fires, i.e. when the download of the response progresses.</dd> -</dl> - -<h2 id="Methods">Methods</h2> - -<p><em>The FetchSignal interface inherits methods from its parent interface, {{domxref("EventTarget")}}.</em></p> - -<h2 id="Examples">Examples</h2> - -<p>In the following snippet, we create a new {{domxref("FetchController")}} object, get its <code>signal</code>, and then give the signal to the <a href="/en-US/docs/Web/API/WindowOrWorkerGlobalScope/fetch">fetch request</a> via the signal parameter of its <code>init</code> object so the controller can control it. Later on we specify an event listener on a cancel button so that when the button is clicked, we abort the fetch request using {{domxref("FetchController.abort()")}}.</p> - -<p>We also specify an observe property inside the fetch request <code>init</code> object — this contains a {{domxref("ObserverCallback")}} object, the sole purpose of which is to provide a callback function that runs when the fetch request runs. This returns a {{domxref("FetchObserver")}} object that can be used to retrieve information concerning the status of a fetch request.</p> - -<p>Here we use {{domxref("FetchController.responseprogress")}} and {{domxref("FetchController.onstatechange")}} event handlers to respectively fill up a progress bar as more of the reponse downloads, and to determine when the download has completed and display a message to let the user know.</p> - -<p><strong>Note that these event handlers are not yet supported anywhere.</strong></p> - -<pre class="brush: js">var controller = new FetchController(); -var signal = controller.signal; - -downloadBtn.addEventListener('click', function() { - fetch(url, { - signal, - observe(observer) { - observer.onresponseprogress = function(e) { - progress.max = e.total; - progress.value = e.loaded; - } - - observer.onstatechange = function() { - if (observer.state = 'complete') { - reports.textContent = 'Download complete'; - } - } - } - }).then( ... ) // do something with the response -}); - -cancelBtn.addEventListener('click', function() { - controller.abort(); -});</pre> - -<p>You can find a work-in-progress demo showing usage of <code>FetchObserver</code> on GitHub (see the <a href="https://github.com/mdn/fetch-examples/tree/master/fetch-signal-controller-observer">source code</a> and the <a href="https://mdn.github.io/fetch-examples/fetch-signal-controller-observer/">live example</a>).</p> - -<h2 id="Specifications">Specifications</h2> - -<p>Not part of a specification yet.</p> - -<h2 id="Browser_compatibility">Browser compatibility</h2> - -<p>{{CompatibilityTable}}</p> - -<div id="compat-desktop"> -<table class="compat-table"> - <tbody> - <tr> - <th>Feature</th> - <th>Chrome</th> - <th>Edge</th> - <th>Firefox (Gecko)</th> - <th>Internet Explorer</th> - <th>Opera</th> - <th>Safari (WebKit)</th> - </tr> - <tr> - <td>Basic support</td> - <td> - <p>{{CompatNo}}</p> - </td> - <td>{{CompatNo}}</td> - <td>{{CompatNo}}<sup>[1]</sup></td> - <td>{{CompatNo}}</td> - <td> - <p>{{CompatNo}}</p> - </td> - <td>{{CompatNo}}</td> - </tr> - </tbody> -</table> -</div> - -<div id="compat-mobile"> -<table class="compat-table"> - <tbody> - <tr> - <th>Feature</th> - <th>Android</th> - <th>Android Webview</th> - <th>Edge</th> - <th>Firefox Mobile (Gecko)</th> - <th>IE Phone</th> - <th>Opera Mobile</th> - <th>Safari Mobile</th> - <th>Chrome for Android</th> - </tr> - <tr> - <td>Basic support</td> - <td>{{CompatNo}}</td> - <td>{{CompatNo}}</td> - <td>{{CompatNo}}</td> - <td>{{CompatNo}}<sup>[1]</sup></td> - <td>{{CompatNo}}</td> - <td>{{CompatNo}}</td> - <td>{{CompatNo}}</td> - <td>{{CompatNo}}</td> - </tr> - </tbody> -</table> -</div> - -<p>[1] Hidden behind a preference in 55+ Nightly. In about:config, you need to create two new boolean prefs — <code>dom.fetchObserver.enabled</code> and <code>dom.fetchController.enabled</code> — and set the values of both to <code>true</code>.</p> - -<h2 id="See_also">See also</h2> - -<ul> - <li><a href="/en-US/docs/Web/API/ServiceWorker_API">ServiceWorker API</a></li> - <li><a href="/en-US/docs/Web/HTTP/Access_control_CORS">HTTP access control (CORS)</a></li> - <li><a href="/en-US/docs/Web/HTTP">HTTP</a></li> -</ul> |