aboutsummaryrefslogtreecommitdiff
path: root/files/zh-cn/web/javascript/reference/global_objects/map/has/index.html
diff options
context:
space:
mode:
Diffstat (limited to 'files/zh-cn/web/javascript/reference/global_objects/map/has/index.html')
-rw-r--r--files/zh-cn/web/javascript/reference/global_objects/map/has/index.html120
1 files changed, 120 insertions, 0 deletions
diff --git a/files/zh-cn/web/javascript/reference/global_objects/map/has/index.html b/files/zh-cn/web/javascript/reference/global_objects/map/has/index.html
new file mode 100644
index 0000000000..73eb4550d0
--- /dev/null
+++ b/files/zh-cn/web/javascript/reference/global_objects/map/has/index.html
@@ -0,0 +1,120 @@
+---
+title: Map.prototype.has()
+slug: Web/JavaScript/Reference/Global_Objects/Map/has
+tags:
+ - ECMAScript 2015
+ - JavaScript
+ - Map
+ - Method
+ - Reference
+translation_of: Web/JavaScript/Reference/Global_Objects/Map/has
+---
+<div>{{JSRef}}</div>
+
+<p>方法<code><strong>has()</strong></code> 返回一个bool值,用来表明map 中是否存在指定元素.</p>
+
+<h2 id="语法">语法</h2>
+
+<pre class="syntaxbox"><code><em>myMap</em>.has(key);</code></pre>
+
+<h3 id="参数">参数</h3>
+
+<dl>
+ <dt>key</dt>
+ <dd>必填. 用来检测是否存在指定元素的键值.</dd>
+</dl>
+
+<h3 id="返回值">返回值</h3>
+
+<dl>
+ <dt>Boolean</dt>
+ <dd>如果指定元素存在于Map中,则返回true。其他情况返回false</dd>
+</dl>
+
+<h2 id="案例">案例</h2>
+
+<h3 id="使用has方法">使用has方法</h3>
+
+<pre class="brush: js">var myMap = new Map();
+myMap.set("bar", "foo");
+
+myMap.has("bar"); // returns true
+myMap.has("baz"); // returns false
+</pre>
+
+<h2 id="规范列表">规范列表</h2>
+
+<table class="standard-table">
+ <tbody>
+ <tr>
+ <th scope="col">规范名称</th>
+ <th scope="col">Status</th>
+ <th scope="col">Comment</th>
+ </tr>
+ <tr>
+ <td>{{SpecName('ES6', '#sec-map.prototype.has', 'Map.prototype.has')}}</td>
+ <td>{{Spec2('ES6')}}</td>
+ <td>Initial definition.</td>
+ </tr>
+ </tbody>
+</table>
+
+<h2 id="浏览器兼容性">浏览器兼容性</h2>
+
+<p>{{CompatibilityTable}}</p>
+
+<div id="compat-desktop">
+<table class="compat-table">
+ <tbody>
+ <tr>
+ <th>浏览器</th>
+ <th>Chrome谷歌</th>
+ <th>Firefox (Gecko)火狐</th>
+ <th>Internet Explorer</th>
+ <th>Opera</th>
+ <th>Safari</th>
+ </tr>
+ <tr>
+ <td>兼容版本</td>
+ <td>38</td>
+ <td>{{CompatGeckoDesktop("13.0")}}</td>
+ <td>11</td>
+ <td>25</td>
+ <td>7.1</td>
+ </tr>
+ </tbody>
+</table>
+</div>
+
+<div id="compat-mobile">
+<table class="compat-table">
+ <tbody>
+ <tr>
+ <th>浏览器</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>兼容版本</td>
+ <td>{{CompatNo}}</td>
+ <td>38</td>
+ <td>{{CompatGeckoMobile("13.0")}}</td>
+ <td>{{CompatNo}}</td>
+ <td>{{CompatNo}}</td>
+ <td>8</td>
+ </tr>
+ </tbody>
+</table>
+</div>
+
+<h2 id="相关链接">相关链接</h2>
+
+<ul>
+ <li>{{jsxref("Map")}}</li>
+ <li>{{jsxref("Map.prototype.set()")}}</li>
+ <li>{{jsxref("Map.prototype.get()")}}</li>
+</ul>