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---
title: 運算子
slug: >-
conflicting/Web/JavaScript/Guide/Expressions_and_Operators_e6fc14473511cf01e7062dfb7751f49d
translation_of: Web/JavaScript/Guide/Expressions_and_Operators
translation_of_original: Web/JavaScript/Guide/Obsolete_Pages/Operators
original_slug: Web/JavaScript/Obsolete_Pages/Obsolete_Pages/Obsolete_Pages/運算子
---
<p> </p>
<h3 id="運算子" name="運算子">運算子</h3>
<p>JavaScript 有以下幾種運算子。本節說明運算子,且包含有關運算子優先順序的資訊。</p>
<ul> <li><a class="internal" href="/zh_tw/Core_JavaScript_1.5_%E6%95%99%E5%AD%B8/%E9%81%8B%E7%AE%97%E5%AD%90/%E4%BB%A3%E5%85%A5%E9%81%8B%E7%AE%97%E5%AD%90" title="zh tw/Core JavaScript 1.5 教學/運算子/代入運算子">代入運算子</a></li> <li><a class="internal" href="/zh_tw/Core_JavaScript_1.5_%E6%95%99%E5%AD%B8/%E9%81%8B%E7%AE%97%E5%AD%90/%E6%AF%94%E8%BC%83%E9%81%8B%E7%AE%97%E5%AD%90" title="zh tw/Core JavaScript 1.5 教學/運算子/比較運算子">比較運算子</a></li> <li><a class="internal" href="/zh_tw/Core_JavaScript_1.5_%E6%95%99%E5%AD%B8/%E9%81%8B%E7%AE%97%E5%AD%90/%E7%AE%97%E8%A1%93%E9%81%8B%E7%AE%97%E5%AD%90" title="zh tw/Core JavaScript 1.5 教學/運算子/算術運算子">算術運算子</a></li> <li><a class="internal" href="/zh_tw/Core_JavaScript_1.5_%E6%95%99%E5%AD%B8/%E9%81%8B%E7%AE%97%E5%AD%90/%E4%BD%8D%E5%85%83%E9%81%8B%E7%AE%97%E5%AD%90" title="zh tw/Core JavaScript 1.5 教學/運算子/位元運算子">位元運算子</a></li> <li><a class="internal" href="/zh_tw/Core_JavaScript_1.5_%E6%95%99%E5%AD%B8/%E9%81%8B%E7%AE%97%E5%AD%90/%E9%82%8F%E8%BC%AF%E9%81%8B%E7%AE%97%E5%AD%90" title="zh tw/Core JavaScript 1.5 教學/運算子/邏輯運算子">邏輯運算子</a></li> <li><a class="internal" href="/zh_tw/Core_JavaScript_1.5_%E6%95%99%E5%AD%B8/%E9%81%8B%E7%AE%97%E5%AD%90/%E5%AD%97%E4%B8%B2%E9%81%8B%E7%AE%97%E5%AD%90" title="zh tw/Core JavaScript 1.5 教學/運算子/字串運算子">字串運算子</a></li> <li><a class="internal" href="/zh_tw/Core_JavaScript_1.5_%E6%95%99%E5%AD%B8/%E9%81%8B%E7%AE%97%E5%AD%90/%E7%89%B9%E6%AE%8A%E9%81%8B%E7%AE%97%E5%AD%90" title="zh tw/Core JavaScript 1.5 教學/運算子/特殊運算子">特殊運算子</a></li>
</ul>
<p>JavaScript 有一元和二元兩種運算子,以及特殊的三元運算子,也就是條件運算子。二元運算子需要兩個運算元,一個在運算子之前,一個在運算子之後︰</p>
<pre>operand1 operator operand2
</pre>
<p>例如,<code>3+4</code> 或 <code>x*y</code>。</p>
<p>一元運算子需要一個運算元,可以運算子之前或之後︰</p>
<pre>operator operand
</pre>
<p>或</p>
<pre>operand operator
</pre>
<p><span style="font-family: monospace;">例如,</span><code>x++</code> 或 <code>++x</code>。</p>
<h4 id="運算子的優先順序" name="運算子的優先順序">運算子的優先順序</h4>
<p><small><em>按照<a href="/Talk:en/Core_JavaScript_1.5_Guide/Operators#Precedence_Table" title="Talk:en/Core_JavaScript_1.5_Guide/Operators#Precedence_Table">相關的討論</a>,本表採用<strong>由高到低</strong>的優先順序。</em></small></p>
<table class="fullwidth-table"> <tbody> <tr> <th>運算子類型</th> <th>單獨的運算子</th> </tr> <tr> <td>成員</td> <td>. []</td> </tr> <tr> <td>呼叫 / 建立實體</td> <td>() new</td> </tr> <tr> <td>反轉 / 遞增</td> <td>! ~ - + ++ -- typeof void delete</td> </tr> <tr> <td>乘法 / 除法</td> <td>* / %</td> </tr> <tr> <td>加法 / 減法</td> <td>+ -</td> </tr> <tr> <td>位元位移</td> <td><< >> >>></td> </tr> <tr> <td>關係</td> <td>< <= > >= in instanceof</td> </tr> <tr> <td>等價</td> <td>== != === !==</td> </tr> <tr> <td>位元 AND</td> <td>&</td> </tr> <tr> <td>位元 XOR</td> <td>^</td> </tr> <tr> <td>位元 OR</td> <td>|</td> </tr> <tr> <td>邏輯 AND</td> <td>&&</td> </tr> <tr> <td>邏輯 OR</td> <td>||</td> </tr> <tr> <td>條件</td> <td>?:</td> </tr> <tr> <td>代入</td> <td>= += -= *= /= %= <<= >>= >>>= &= ^= |=</td> </tr> <tr> <td>逗號</td> <td>,</td> </tr> </tbody>
</table>
<p><small><strong>表 3.1: 運算子的優先順序</strong></small></p>
<p>有關本表的詳細版本,且附有關於運算子的完整細節,請參閱 <a class="internal" href="/zh_tw/Core_JavaScript_1.5_%E5%8F%83%E8%80%83/%E9%81%8B%E7%AE%97%E5%AD%90/%E9%81%8B%E7%AE%97%E5%AD%90%E7%9A%84%E5%84%AA%E5%85%88%E9%A0%86%E5%BA%8F#%E8%A1%A8" title="zh tw/Core JavaScript 1.5 參考/運算子/運算子的優先順序#表">參考的章節</a>。</p>
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