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command-line-arguments.html
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Go by Example 中文版: 命令行参数</title>
<link rel=stylesheet href="site.css">
</head>
<script>
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if (e.key == "ArrowLeft") {
window.location.href = 'testing-and-benchmarking';
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<body>
<div class="example" id="command-line-arguments">
<h2><a href="./">Go by Example 中文版</a>: 命令行参数</h2>
<table>
<tr>
<td class="docs">
<p><a href="http://en.wikipedia.org/wiki/Command-line_interface#Arguments"><em>命令行参数</em></a>
是指定程序运行参数的一个常见方式。例如，<code>go run hello.go</code>，
程序 <code>go</code> 使用了 <code>run</code> 和 <code>hello.go</code> 两个参数。</p>
</td>
<td class="code empty leading">
</td>
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<tr>
<td class="docs">
</td>
<td class="code leading">
<a href="https://play.studygolang.com/p/ZDt7THZQ344"><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>
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<td class="docs">
</td>
<td class="code leading">
<pre class="chroma"><span class="kn">import</span> <span class="p">(</span>
<span class="s">"fmt"</span>
<span class="s">"os"</span>
<span class="p">)</span>
</pre>
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</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><code>os.Args</code> 提供原始命令行参数访问功能。
注意，切片中的第一个参数是该程序的路径，
而 <code>os.Args[1:]</code>保存了程序全部的参数。</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="nx">argsWithProg</span> <span class="o">:=</span> <span class="nx">os</span><span class="p">.</span><span class="nx">Args</span>
<span class="nx">argsWithoutProg</span> <span class="o">:=</span> <span class="nx">os</span><span class="p">.</span><span class="nx">Args</span><span class="p">[</span><span class="mi">1</span><span class="p">:]</span>
</pre>
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</tr>
<tr>
<td class="docs">
<p>你可以使用标准的下标方式取得单个参数的值。</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="nx">arg</span> <span class="o">:=</span> <span class="nx">os</span><span class="p">.</span><span class="nx">Args</span><span class="p">[</span><span class="mi">3</span><span class="p">]</span>
</pre>
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<td class="docs">
</td>
<td class="code">
<pre class="chroma"> <span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="nx">argsWithProg</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">argsWithoutProg</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">arg</span><span class="p">)</span>
<span class="p">}</span>
</pre>
</td>
</tr>
</table>
<table>
<tr>
<td class="docs">
<p>要实验命令行参数，最好先使用 <code>go build</code> 编译一个可执行二进制文件</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="gp">$</span> go build command-line-arguments.go
<span class="gp">$</span> ./command-line-arguments a b c d
<span class="go">[./command-line-arguments a b c d]
</span><span class="go">[a b c d]
</span><span class="go">c</span></pre>
</td>
</tr>
<tr>
<td class="docs">
<p>下面我们要看看更高级的使用标记的命令行处理方法。</p>
</td>
<td class="code empty">
</td>
</tr>
</table>
<p class="next">
下一个例子: <a href="command-line-flags.html">命令行标志</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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