path: root/files/zh-cn/web/javascript/reference/global_objects/string/match/index.html

---
title: String.prototype.match()
slug: Web/JavaScript/Reference/Global_Objects/String/match
translation_of: Web/JavaScript/Reference/Global_Objects/String/match
---
<p>{{JSRef}}</p>

<p> <strong><code>match()</code> </strong>方法检索返回一个字符串匹配正则表达式的结果。</p>


<div>{{EmbedInteractiveExample("pages/js/string-match.html", "shorter")}}</div>

<div class="hidden">The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone <a href="https://github.com/mdn/interactive-examples">https://github.com/mdn/interactive-examples</a> and send us a pull request.</div>

<h2 id="Syntax" name="Syntax">语法</h2>

<pre class="syntaxbox notranslate"><code><em>str</em>.match(regexp)</code></pre>

<h3 id="Parameters" name="Parameters">参数</h3>

<dl>
 <dt><code>regexp</code></dt>
 <dd>一个<a href="/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/RegExp" title="JavaScript/Reference/Global Objects/RegExp">正则表达式</a>对象。如果传入一个非正则表达式对象，则会隐式地使用 <code>new RegExp(obj)</code> 将其转换为一个 {{jsxref("RegExp")}} 。如果你没有给出任何参数并直接使用match() 方法 ，你将会得到一 个包含空字符串的 {{jsxref("Array")}} ：[""] 。</dd>
</dl>

<h3 id="返回值">返回值</h3>

<ul>
 <li><span style="line-height: 1.572;">如果使用g标志，则将返回与完整正则表达式匹配的所有结果，但不会返回捕获组。</span></li>
 <li>如果未使用g标志，则仅返回第一个完整匹配及其相关的捕获组<span style="line-height: 1.572;">（<code>Array</code>）</span>。 在这种情况下，返回的项目将具有如下所述的其他属性。</li>
</ul>

<h4 id="附加属性">附加属性</h4>

<p>如上所述，匹配的结果包含如下所述的附加特性。</p>

<ul>
 <li><code>groups</code>: 一个捕获组数组 或 {{jsxref("undefined")}}（如果没有定义命名捕获组）。</li>
 <li><code>index</code>: 匹配的结果的开始位置</li>
 <li><code>input</code>: 搜索的字符串.</li>
</ul>

<dl>
 <dd>一个{{jsxref("Array")}}，其内容取决于global（<code>g</code>）标志的存在与否，如果未找到匹配则为{{jsxref("null")}}。</dd>
</dl>

<h2 id="Description" name="Description">描述</h2>

<p>如果正则表达式不包含 <code>g </code>标志，<code>str.match()</code> 将返回与 {{jsxref("RegExp.prototype.exec()", "RegExp.exec()")}}. 相同的结果。</p>

<h3 id="Notes" name="Notes">参看：<code>RegExp</code> 方法</h3>

<ul>
 <li>如果你需要知道一个字符串是否与一个正则表达式匹配 {{jsxref("RegExp")}} ，可使用 {{jsxref("RegExp.prototype.test()", "RegExp.test()")}} 。</li>
 <li>如果你只是需要第一个匹配结果，你也可以使用 {{jsxref("RegExp.prototype.exec()", "RegExp.exec()")}} 。</li>
 <li>如果你想要获得捕获组，并且设置了全局标志，你需要用 {{jsxref("RegExp.prototype.exec()", "RegExp.exec()")}}  或者 {{jsxref("String.prototype.matchAll()", " String.prototype.matchAll()")}}</li>
</ul>

<h2 id="Examples" name="Examples">示例</h2>

<h3 id="Example_Using_match" name="Example:_Using_match">例子：使用 <code>match</code></h3>

<p>在下例中，使用 <code>match</code> 查找 "<code>Chapter</code>" 紧跟着 1 个或多个数值字符，再紧跟着一个小数点和数值字符 0 次或多次。正则表达式包含 <code>i</code> 标志，因此大小写会被忽略。</p>

<pre class="brush: js line-numbers  language-js notranslate"><code class="language-js"><span class="keyword token">var</span> str <span class="operator token">=</span> <span class="string token">'For more information, see Chapter 3.4.5.1'</span><span class="punctuation token">;</span>
<span class="keyword token">var</span> re <span class="operator token">=</span> <span class="regex token">/see (chapter \d+(\.\d)*)/i</span><span class="punctuation token">;</span>
<span class="keyword token">var</span> found <span class="operator token">=</span> str<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span>re<span class="punctuation token">)</span><span class="punctuation token">;</span>

console<span class="punctuation token">.</span><span class="function token">log</span><span class="punctuation token">(</span>found<span class="punctuation token">)</span><span class="punctuation token">;</span>

<span class="comment token">// logs [ 'see Chapter 3.4.5.1',</span>
<span class="comment token">//        'Chapter 3.4.5.1',</span>
<span class="comment token">//        '.1',</span>
<span class="comment token">//        index: 22,</span>
<span class="comment token">//        input: 'For more information, see Chapter 3.4.5.1' ]</span>

<span class="comment token">// 'see Chapter 3.4.5.1' 是整个匹配。</span>
<span class="comment token">// 'Chapter 3.4.5.1' 被'(chapter \d+(\.\d)*)'捕获。</span>
<span class="comment token">// '.1' 是被'(\.\d)'捕获的最后一个值。</span>
<span class="comment token">// 'index' 属性(22) 是整个匹配从零开始的索引。</span>
<span class="comment token">// 'input' 属性是被解析的原始字符串。</span></code></pre>

<h3 id="Example_Using_global_and_ignore_case_flags_with_match" name="Example:_Using_global_and_ignore_case_flags_with_match">例子：<code>match</code> 使用全局（global）和忽略大小写（ignore case）标志</h3>

<p>下例展示了 <code>match</code> 使用 global 和 ignore case 标志。A-E、a-e 的所有字母将会作为一个数组的元素返回。</p>

<pre class="brush: js line-numbers  language-js notranslate"><code class="language-js"><span class="keyword token">var</span> str <span class="operator token">=</span> <span class="string token">'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'</span><span class="punctuation token">;</span>
<span class="keyword token">var</span> regexp <span class="operator token">=</span> <span class="regex token">/[A-E]/gi</span><span class="punctuation token">;</span>
<span class="keyword token">var</span> matches_array <span class="operator token">=</span> str<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span>regexp<span class="punctuation token">)</span><span class="punctuation token">;</span>

console<span class="punctuation token">.</span><span class="function token">log</span><span class="punctuation token">(</span>matches_array<span class="punctuation token">)</span><span class="punctuation token">;</span>
<span class="comment token">// ['A', 'B', 'C', 'D', 'E', 'a', 'b', 'c', 'd', 'e']</span></code></pre>

<h3 id="使用match，不传参数"><code>使用match()，不传参数 </code></h3>

<pre class="brush: js line-numbers  language-js notranslate"><code class="language-js"><span class="keyword token">var</span> str <span class="operator token">=</span> <span class="string token">"Nothing will come of nothing."</span><span class="punctuation token">;</span>

str<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span><span class="punctuation token">)</span><span class="punctuation token">;</span>   <span class="comment token">// returns [""]</span></code></pre>

<h3 id="一个非正则表达式对象作为参数">一个非正则表达式对象作为参数</h3>

<p>当参数是一个字符串或一个数字，它会使用new RegExp(obj)来隐式转换成一个 {{jsxref("RegExp")}}。如果它是一个有正号的正数，RegExp() 方法将忽略正号。</p>

<pre class="brush: js line-numbers  language-js notranslate"><code class="language-js"><span class="keyword token">var</span> str1 <span class="operator token">=</span> <span class="string token">"NaN means not a number. Infinity contains -Infinity and +Infinity in JavaScript."</span><span class="punctuation token">,</span>
    str2 <span class="operator token">=</span> <span class="string token">"My grandfather is 65 years old and My grandmother is 63 years old."</span><span class="punctuation token">,</span>
    str3 <span class="operator token">=</span> <span class="string token">"The contract was declared null and void."</span><span class="punctuation token">;</span>
str1<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span><span class="string token">"number"</span><span class="punctuation token">)</span><span class="punctuation token">;</span>   <span class="comment token">// "number" 是字符串。返回["number"]</span>
str1<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span><span class="number token">NaN</span><span class="punctuation token">)</span><span class="punctuation token">;</span>        <span class="comment token">// NaN的类型是number。返回["NaN"]</span>
str1<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span><span class="number token">Infinity</span><span class="punctuation token">)</span><span class="punctuation token">;</span>   <span class="comment token">// Infinity的类型是number。返回["Infinity"]</span>
str1<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span><span class="operator token">+</span><span class="number token">Infinity</span><span class="punctuation token">)</span><span class="punctuation token">;</span>  <span class="comment token">// 返回["Infinity"]</span>
str1<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span><span class="operator token">-</span><span class="number token">Infinity</span><span class="punctuation token">)</span><span class="punctuation token">;</span>  <span class="comment token">// 返回["-Infinity"]</span>
str2<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span><span class="number token">65</span><span class="punctuation token">)</span><span class="punctuation token">;</span>         <span class="comment token">// 返回["65"]</span>
str2<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span><span class="operator token">+</span><span class="number token">65</span><span class="punctuation token">)</span><span class="punctuation token">;</span>        <span class="comment token">// 有正号的number。返回["65"]</span>
str3<span class="punctuation token">.</span><span class="function token">match</span><span class="punctuation token">(</span><span class="keyword token">null</span><span class="punctuation token">)</span><span class="punctuation token">;</span>       <span class="comment token">// 返回["null"]</span></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>{{SpecName('ES3')}}</td>
   <td>{{Spec2('ES3')}}</td>
   <td>Initial definition. Implemented in JavaScript 1.2.</td>
  </tr>
  <tr>
   <td>{{SpecName('ES5.1', '#sec-15.5.4.10', 'String.prototype.match')}}</td>
   <td>{{Spec2('ES5.1')}}</td>
   <td></td>
  </tr>
  <tr>
   <td>{{SpecName('ES6', '#sec-string.prototype.match', 'String.prototype.match')}}</td>
   <td>{{Spec2('ES6')}}</td>
   <td></td>
  </tr>
  <tr>
   <td>{{SpecName('ESDraft', '#sec-string.prototype.match', 'String.prototype.match')}}</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>

<p>{{ CompatibilityTable() }}</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>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</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>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
  </tr>
 </tbody>
</table>
</div>

<h2 id="Firefox_特殊注意">Firefox 特殊注意</h2>

<ul>
 <li>从Gecko 27 {{geckoRelease(27)}}开始，此方法遵守ECMAScript 规范。当使用全局正则表达式调用 <code>match()时，</code>{{jsxref("RegExp.lastIndex")}} 属性(如果指定)会重置为 <code>0</code> ({{bug(501739)}})。</li>
 <li>从 Gecko 39 {{geckoRelease(39)}}开始，不赞成使用非标准的标志参数，并抛出一个控制台警告({{bug(1142351)}})。</li>
 <li>从 Gecko 47 {{geckoRelease(47)}} 开始 ， non-release builds不再支持非标准的标志参数，并且将完全移除({{bug(1245801)}})。</li>
 <li>从 Gecko 49 {{geckoRelease(49)}} 开始 ， 不再支持非标准的标志参数 ({{bug(1108382)}}).</li>
</ul>

<h2 id="See_also" name="See_also">相关链接</h2>

<ul>
 <li>{{jsxref("RegExp")}}</li>
 <li>{{jsxref("RegExp.prototype.exec()")}}</li>
 <li>{{jsxref("RegExp.prototype.test()")}}</li>
</ul>