-
Notifications
You must be signed in to change notification settings - Fork 8
/
range-over-channels.html
155 lines (116 loc) · 5.3 KB
/
range-over-channels.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Go by Example 中文版: 通道遍历</title>
<link rel=stylesheet href="site.css">
</head>
<script>
onkeydown = (e) => {
if (e.key == "ArrowLeft") {
window.location.href = 'closing-channels';
}
if (e.key == "ArrowRight") {
window.location.href = 'timers';
}
}
</script>
<body>
<div class="example" id="range-over-channels">
<h2><a href="./">Go by Example 中文版</a>: 通道遍历</h2>
<table>
<tr>
<td class="docs">
<p>在<a href="range">前面</a>的例子中，
我们讲过 <code>for</code> 和 <code>range</code> 为基本的数据结构提供了迭代的功能。
我们也可以使用这个语法来遍历的从通道中取值。</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/_BUOq0aiP3r"><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">
</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>我们将遍历在 <code>queue</code> 通道中的两个值。</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="nx">queue</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> <span class="mi">2</span><span class="p">)</span>
<span class="nx">queue</span> <span class="o"><-</span> <span class="s">"one"</span>
<span class="nx">queue</span> <span class="o"><-</span> <span class="s">"two"</span>
<span class="nb">close</span><span class="p">(</span><span class="nx">queue</span><span class="p">)</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p><code>range</code> 迭代从 <code>queue</code> 中得到每个值。
因为我们在前面 <code>close</code> 了这个通道，所以，这个迭代会在接收完 2 个值之后结束。</p>
</td>
<td class="code">
<pre class="chroma">
<span class="k">for</span> <span class="nx">elem</span> <span class="o">:=</span> <span class="k">range</span> <span class="nx">queue</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">elem</span><span class="p">)</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 range-over-channels.go
<span class="go">one
</span><span class="go">two</span></pre>
</td>
</tr>
<tr>
<td class="docs">
<p>这个例子也让我们看到，一个非空的通道也是可以关闭的，
并且，通道中剩下的值仍然可以被接收到。</p>
</td>
<td class="code empty">
</td>
</tr>
</table>
<p class="next">
下一个例子: <a href="timers">Timer</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>
var codeLines = [];
codeLines.push('');codeLines.push('package main\u000A');codeLines.push('import \"fmt\"\u000A');codeLines.push('func main() {\u000A');codeLines.push(' queue :\u003D make(chan string, 2)\u000A queue \u003C- \"one\"\u000A queue \u003C- \"two\"\u000A close(queue)\u000A');codeLines.push(' for elem :\u003D range queue {\u000A fmt.Println(elem)\u000A }\u000A}\u000A');codeLines.push('');codeLines.push('');
</script>
<script src="site.js" async></script>
</body>
</html>