32 lines
819 B
Markdown
32 lines
819 B
Markdown
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---
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title: Foreach Loop
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localeTitle: Foreach循环
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---
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## Foreach循环
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`foreach`循环为集合中的每个项执行一段代码。 `foreach`循环的好处是你不需要知道集合中有多少项来迭代它;你只需告诉你的`foreach`循环遍历集合，只要其中有项目。它对于遍历列表，数组，数据表，IEnumerables和其他类似列表的数据结构非常有用。它可能比设计精良`for`环路效率低，但在大多数情况下差异可以忽略不计。
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### 例
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```csharp
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foreach (element in iterable-item)
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{
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// body of foreach loop
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}
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List<string> Names = new List<string>{ "Jim", "Jane", "Jack" }
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foreach(string name in Names)
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{
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Console.WriteLine("We have " + name);
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}
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```
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### 输出：
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```sh
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> We have Jim
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> We have Jane
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> We have Jack
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```
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