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channels.html
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Go by Example 中文版: 通道</title>
<link rel=stylesheet href="site.css">
</head>
<script>
onkeydown = (e) => {
if (e.key == "ArrowLeft") {
window.location.href = 'goroutines';
}
if (e.key == "ArrowRight") {
window.location.href = 'channel-buffering';
}
}
</script>
<body>
<div class="example" id="channels">
<h2><a href="./">Go by Example 中文版</a>: 通道</h2>
<table>
<tr>
<td class="docs">
<p><em>通道(channels)</em> 是连接多个协程的管道。
你可以从一个协程将值发送到通道，然后在另一个协程中接收。</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/BSqrJN1MQAX"><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>
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<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>使用 <code>make(chan val-type)</code> 创建一个新的通道。
通道类型就是他们需要传递值的类型。</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="nx">messages</span> <span class="o">:=</span> <span class="nb">make</span><span class="p">(</span><span class="kd">chan</span> <span class="kt">string</span><span class="p">)</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p>使用 <code>channel <-</code> 语法 <em>发送</em> 一个新的值到通道中。
这里我们在一个新的协程中发送 <code>"ping"</code> 到上面创建的 <code>messages</code> 通道中。</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="k">go</span> <span class="kd">func</span><span class="p">()</span> <span class="p">{</span> <span class="nx">messages</span> <span class="o"><-</span> <span class="s">"ping"</span> <span class="p">}()</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p>使用 <code><-channel</code> 语法从通道中 <em>接收</em> 一个值。
这里我们会收到在上面发送的 <code>"ping"</code> 消息并将其打印出来。</p>
</td>
<td class="code">
<pre class="chroma">
<span class="nx">msg</span> <span class="o">:=</span> <span class="o"><-</span><span class="nx">messages</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="nx">msg</span><span class="p">)</span>
<span class="p">}</span>
</pre>
</td>
</tr>
</table>
<table>
<tr>
<td class="docs">
<p>我们运行程序时，通过通道，
成功的将消息 <code>"ping"</code> 从一个协程传送到了另一个协程中。</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="gp">$</span> go run channels.go
<span class="go">ping</span></pre>
</td>
</tr>
<tr>
<td class="docs">
<p>默认发送和接收操作是阻塞的，直到发送方和接收方都就绪。
这个特性允许我们，不使用任何其它的同步操作，
就可以在程序结尾处等待消息 <code>"ping"</code>。</p>
</td>
<td class="code empty">
</td>
</tr>
</table>
<p class="next">
下一个例子: <a href="channel-buffering">通道缓冲</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>
<script>
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codeLines.push('');codeLines.push('package main\u000A');codeLines.push('import \"fmt\"\u000A');codeLines.push('func main() {\u000A');codeLines.push(' messages :\u003D make(chan string)\u000A');codeLines.push(' go func() { messages \u003C- \"ping\" }()\u000A');codeLines.push(' msg :\u003D \u003C-messages\u000A fmt.Println(msg)\u000A}\u000A');codeLines.push('');codeLines.push('');
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<script src="site.js" async></script>
</body>
</html>