blob: 9fb4ae67ae1a132481be1b307202830d9033c1db (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
---
title: Set.prototype.clear()
slug: Web/JavaScript/Reference/Global_Objects/Set/clear
tags:
- ECMAScript6
- JavaScript
- Prototype
- set
- 原型
- 方法
translation_of: Web/JavaScript/Reference/Global_Objects/Set/clear
---
<div>{{JSRef}}</div>
<p><code><strong>clear()</strong></code> 方法用来清空一个 <code>Set</code> 对象中的所有元素。</p>
<h2 id="Syntax">语法</h2>
<pre class="syntaxbox"><code><em>mySet</em>.clear();</code>
</pre>
<h3 id="返回值">返回值</h3>
<p>{{jsxref("undefined")}}.</p>
<h2 id="Examples">示例</h2>
<pre class="brush: js">var mySet = new Set();
mySet.add(1);
mySet.add("foo");
mySet.size; // 2
mySet.has("foo"); // true
mySet.clear();
mySet.size; // 0
mySet.has("bar") // false
</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>{{SpecName('ES6', '#sec-set.prototype.clear', 'Set.prototype.clear')}}</td>
<td>{{Spec2('ES6')}}</td>
<td>Initial definition.</td>
</tr>
<tr>
<td>{{SpecName('ESDraft', '#sec-set.prototype.clear', 'Set.prototype.clear')}}</td>
<td>{{Spec2('ESDraft')}}</td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="浏览器兼容性">浏览器兼容性</h2>
{{Compat}}
<h2 id="相关链接"><strong>相关链接</strong></h2>
<ul>
<li>{{jsxref("Set")}}</li>
<li>{{jsxref("Set.prototype.delete()")}}</li>
</ul>
|
