uTools-Manuals/docs/javascript/Reference/Global_Objects/WeakMap/set.html

<article id="wikiArticle">
<div></div>
<p><code><strong>set()</strong></code> 方法根据指定的<code>key和</code><code>value在</code> <code>WeakMap对象中添加新/更新元素。</code></p>
<h2 id="语法">语法</h2>
<pre><code class="language-javascript"><code><em>wm</em>.set(key, value);</code></code></pre>
<h3 id="参数">参数</h3>
<dl>
<dt>key</dt>
<dd>必须的。是要在<code>WeakMap</code> 对象中添加/更新元素的key部分。</dd>
<dt>value</dt>
<dd>必须的。是要在<code>WeakMap</code> 对象中添加/更新元素的value部分<code>。</code></dd>
</dl>
<h3 id="返回值">返回值</h3>
<p><code>该WeakMap对象</code></p>
<h2 id="例子">例子</h2>
<h3 id="使用set方法"><code>使用set方法</code></h3>
<pre><code  class="language-javascript">var wm = new WeakMap();
var obj = {};

// Add new elements to the WeakMap
wm.set(obj, "foo").set(window, "bar"); // chainable

// Update an element in the WeakMap
wm.set(obj, "baz");
</code></pre>
<h2 id="规范">规范</h2>
<table class="standard-table">
<tbody>
<tr>
<th scope="col">Specification</th>
<th scope="col">Status</th>
<th scope="col">Comment</th>
</tr>
<tr>
<td><a class="external" href="https://www.ecma-international.org/ecma-262/6.0/#sec-weakmap.prototype.set" hreflang="en" lang="en" rel="noopener">ECMAScript 2015 (6th Edition, ECMA-262)<br/><small lang="zh-CN">WeakMap.prototype.set</small></a></td>
<td><span class="spec-Standard">Standard</span></td>
<td>Initial definition.</td>
</tr>
<tr>
<td><a class="external" href="https://tc39.github.io/ecma262/#sec-weakmap.prototype.set" hreflang="en" lang="en" rel="noopener">ECMAScript Latest Draft (ECMA-262)<br/><small lang="zh-CN">WeakMap.prototype.set</small></a></td>
<td><span class="spec-Draft">Draft</span></td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="浏览器兼容">浏览器兼容</h2>
<p></p><div class="blockIndicator warning"><strong><a class="external" href="https://github.com/mdn/browser-compat-data" rel="noopener">We're converting our compatibility data into a machine-readable JSON format</a></strong>.
            This compatibility table still uses the old format,
            because we haven't yet converted the data it contains.
            <strong><a class="new" href="/zh-CN/docs/MDN/Contribute/Structures/Compatibility_tables" rel="nofollow">Find out how you can help!</a></strong></div>
<div class="htab">
<a id="AutoCompatibilityTable" name="AutoCompatibilityTable"></a>
<ul>
<li class="selected"><a>Desktop</a></li>
<li><a>Mobile</a></li>
</ul>
</div><p></p>
<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>36</td>
<td><a href="/en-US/Firefox/Releases/6" title="Released on 2011-08-16.">6.0</a> (6.0)</td>
<td>11</td>
<td>23</td>
<td>7.1</td>
</tr>
</tbody>
</table>
</div>
<div id="compat-mobile">
<table class="compat-table">
<tbody>
<tr>
<th>Feature</th>
<th>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><span style="color: #f00;">未实现</span></td>
<td>6.0 (6.0)</td>
<td><span style="color: #f00;">未实现</span></td>
<td><span style="color: #f00;">未实现</span></td>
<td>8</td>
</tr>
</tbody>
</table>
</div>
<h2 id="Firefox-特殊说明">Firefox-特殊说明</h2>
<ul>
<li>直到Firefox 33 (Firefox 33 / Thunderbird 33 / SeaMonkey 2.30), <code>WeakMap.prototype.set</code> returned <code>undefined</code> 而不支持联式。它已经修复 (<a class="external" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1031632" rel="noopener" title="FIXED: Map.prototype.set, WeakMap.prototype.set and Set.prototype.add should be chainable">bug 1031632</a>). 这样的实现也存在于 Chrome/v8 (<a class="external" href="https://code.google.com/p/v8/issues/detail?id=3410" rel="noopener">issue</a>).</li>
</ul>
<h2 id="See_also">See also</h2>
<ul>
<li><a href="Reference/WeakMap" title="此页面仍未被本地化, 期待您的翻译!"><code>WeakMap</code></a></li>
<li><a href="Reference/Global_Objects/WeakMap/get" title="get() 方法返回  WeakMap 指定的元素。"><code>WeakMap.prototype.get()</code></a></li>
<li><a href="Reference/Global_Objects/WeakMap/has" title="has() 方法根据WeakMap对象的元素中是否存在key键返回一个boolean值。"><code>WeakMap.prototype.has()</code></a></li>
</ul>
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