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diff --git a/files/zh-cn/web/javascript/reference/global_objects/object/observe/index.html b/files/zh-cn/web/javascript/reference/global_objects/object/observe/index.html new file mode 100644 index 0000000000..e37cc6ab6f --- /dev/null +++ b/files/zh-cn/web/javascript/reference/global_objects/object/observe/index.html @@ -0,0 +1,160 @@ +--- +title: Object.observe() +slug: Web/JavaScript/Reference/Global_Objects/Object/observe +tags: + - ECMAScript7 + - Experimental + - JavaScript + - Method + - Object + - observe +translation_of: Archive/Web/JavaScript/Object.observe +--- +<div>{{JSRef}} {{obsolete_header}}</div> + +<h2 id="概述">概述</h2> + +<p><strong><code>Object.observe()</code></strong> 方法用于异步地监视一个对象的修改。当对象属性被修改时,方法的回调函数会提供一个有序的修改流。然而,这个接口已经被废弃并从各浏览器中移除。你可以使用更通用的 {{jsxref("Proxy")}} 对象替代。</p> + +<h2 id="语法">语法</h2> + +<pre class="syntaxbox"><code>Object.observe(<var>obj</var>, <var>callback</var></code>[, <var>acceptList</var>])</pre> + +<h3 id="参数">参数</h3> + +<dl> + <dt><code>obj</code></dt> + <dd>被监控的对象.</dd> + <dt><code>callback</code></dt> + <dd>当对象被修改时触发的回调函数,其参数为: + <dl> + <dt><code>changes</code></dt> + <dd>一个数组,其中包含的每一个对象代表一个修改行为。每个修改行为的对象包含: + <ul> + <li><strong><code>name</code></strong>: 被修改的属性名称<span style="font-family: consolas,monaco,andale mono,monospace;">。</span></li> + <li><strong><code>object</code></strong>: 修改后该对象的值<span style="font-family: consolas,monaco,andale mono,monospace;">。</span></li> + <li><strong><code>type</code></strong>: 表示对该对象做了何种类型的修改,可能的值为<code>"add"</code>, <code>"update"</code>, or <code>"delete"</code><span style="font-family: consolas,monaco,andale mono,monospace;">。</span></li> + <li><strong><code>oldValue</code></strong>: 对象修改前的值。该值只在<code>"update"<font face="Open Sans, sans-serif">与</font></code><code>"delete"有效。</code></li> + <li> </li> + </ul> + </dd> + <dt><font face="Consolas">acceptList</font></dt> + <dd>在给定对象上给定回调中要监视的变化类型列表。如果省略, <code><font face="Courier New">["add", "update", "delete", "reconfigure", "setPrototype", "preventExtensions"]</font></code> 将会被使用。</dd> + </dl> + </dd> +</dl> + +<h2 id="描述">描述</h2> + +<p><code style="font-style: normal;">callback</code> 函数会在<code>对象被改变时被调用,其参数为一个包含所有修改信息的有序的数组对象。</code></p> + +<h2 id="例子">例子</h2> + +<h3 id="例子_打印出三种不同操作类型的日志">例子: 打印出三种不同操作类型的日志</h3> + +<pre class="brush: js">var obj = { + foo: 0, + bar: 1 +}; + +Object.observe(obj, function(changes) { + console.log(changes); +}); + +obj.baz = 2; +// [{name: 'baz', object: <obj>, type: 'add'}] + +obj.foo = 'hello'; +// [{name: 'foo', object: <obj>, type: 'update', oldValue: 0}] + +delete obj.baz; +// [{name: 'baz', object: <obj>, type: 'delete', oldValue: 2}] +</pre> + +<h3 id="例子_数据绑定">例子: 数据绑定</h3> + +<pre class="brush: js">// 一个数据模型 +var user = { + id: 0, + name: 'Brendan Eich', + title: 'Mr.' +}; + +// 创建用户的greeting +function updateGreeting() { + user.greeting = 'Hello, ' + user.title + ' ' + user.name + '!'; +} +updateGreeting(); + +Object.observe(user, function(changes) { + changes.forEach(function(change) { + // 当name或title属性改变时, 更新greeting + if (change.name === 'name' || change.name === 'title') { + updateGreeting(); + } + }); +}); +</pre> + +<h2 id="Specifications" name="Specifications">规范</h2> + +<p><a href="https://github.com/arv/ecmascript-object-observe">Strawman proposal for ECMAScript 7</a>.</p> + +<h2 id="Browser_compatibility" name="Browser_compatibility">浏览器兼容性</h2> + +<div>{{CompatibilityTable}}</div> + +<div id="compat-desktop"> +<table class="compat-table"> + <tbody> + <tr> + <th>Feature</th> + <th>Chrome</th> + <th>Firefox (Gecko)</th> + <th>Internet Explorer</th> + <th>Opera</th> + <th>Safari</th> + </tr> + <tr> + <td>Basic support</td> + <td>{{CompatChrome("36")}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatOpera("23")}}</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>Chrome for Android</th> + <th>Firefox Mobile (Gecko)</th> + <th>IE Mobile</th> + <th>Opera Mobile</th> + <th>Safari Mobile</th> + </tr> + <tr> + <td>Basic support</td> + <td>{{CompatNo}}</td> + <td>{{CompatChrome("36")}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatOpera("23")}}</td> + <td>{{CompatNo}}</td> + </tr> + </tbody> +</table> +</div> + +<h2 id="See_also" name="See_also">相关链接</h2> + +<ul> + <li>{{jsxref("Object.unobserve()")}} {{experimental_inline}}</li> + <li>{{jsxref("Array.observe()")}} {{experimental_inline}}</li> +</ul> |
