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multiple-return-values.html
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Go by Example 中文版: 多返回值</title>
<link rel=stylesheet href="site.css">
</head>
<script>
onkeydown = (e) => {
if (e.key == "ArrowLeft") {
window.location.href = 'functions';
}
if (e.key == "ArrowRight") {
window.location.href = 'variadic-functions';
}
}
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<body>
<div class="example" id="multiple-return-values">
<h2><a href="./">Go by Example 中文版</a>: 多返回值</h2>
<table>
<tr>
<td class="docs">
<p>Go 原生支持 _多返回值_。
这个特性在 Go 语言中经常用到，例如用来同时返回一个函数的结果和错误信息。</p>
</td>
<td class="code empty leading">
</td>
</tr>
<tr>
<td class="docs">
</td>
<td class="code leading">
<a href="https://play.studygolang.com/p/1I0q4Z78G-p"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
<pre class="chroma"><span class="kn">package</span> <span class="nx">main</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
</td>
<td class="code leading">
<pre class="chroma"><span class="kn">import</span> <span class="s">"fmt"</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p><code>(int, int)</code> 在这个函数中标志着这个函数返回 2 个 <code>int</code>。</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="kd">func</span> <span class="nf">vals</span><span class="p">()</span> <span class="p">(</span><span class="kt">int</span><span class="p">,</span> <span class="kt">int</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="mi">3</span><span class="p">,</span> <span class="mi">7</span>
<span class="p">}</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
</td>
<td class="code leading">
<pre class="chroma"><span class="kd">func</span> <span class="nf">main</span><span class="p">()</span> <span class="p">{</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p>这里我们通过 <em>多赋值</em> 操作来使用这两个不同的返回值。</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="nx">a</span><span class="p">,</span> <span class="nx">b</span> <span class="o">:=</span> <span class="nf">vals</span><span class="p">()</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="nx">a</span><span class="p">)</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="nx">b</span><span class="p">)</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p>如果你仅仅需要返回值的一部分的话，你可以使用空白标识符 <code>_</code>。</p>
</td>
<td class="code">
<pre class="chroma">
<span class="nx">_</span><span class="p">,</span> <span class="nx">c</span> <span class="o">:=</span> <span class="nf">vals</span><span class="p">()</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="nx">c</span><span class="p">)</span>
<span class="p">}</span>
</pre>
</td>
</tr>
</table>
<table>
<tr>
<td class="docs">
</td>
<td class="code leading">
<pre class="chroma"><span class="gp">$</span> go run multiple-return-values.go
<span class="go">3
</span><span class="go">7
</span><span class="go">7</span></pre>
</td>
</tr>
<tr>
<td class="docs">
<p>我们接下来要学习的是 Go 函数另一个很好的特性：变参函数。</p>
</td>
<td class="code empty">
</td>
</tr>
</table>
<p class="next">
下一个例子: <a href="variadic-functions">变参函数</a>
</p>
<p class="footer">
<a href="https://twitter.com/mmcgrana">@mmcgrana</a> 和<a href="https://eli.thegreenplace.net">Eli Bendersky</a>编写 | <a href="https://github.com/gobyexample-cn">gobyexample-cn</a> 翻译 | <a href="https://github.com/gobyexample-cn/gobyexample/issues">反馈</a> | <a href="https://github.com/gobyexample-cn/gobyexample">源码</a> | <a href="https://github.com/mmcgrana/gobyexample#license">license</a> </p>
</p>
</div>
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</body>
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