47 lines
1.1 KiB
Markdown
47 lines
1.1 KiB
Markdown
|
---
|
|||
|
|
title: For Loop
|
|||
|
|
localeTitle: 对于循环
|
|||
|
|
---
|
|||
|
|
# 对于循环
|
|||
|
|
|
|||
|
|
`for`循环执行代码块，直到指定的条件为false。虽然`for`循环看起来像[`while`循环](https://guide.freecodecamp.org/csharp/while-loop) ，但开发人员应该**正确**使用它们。当迭代次数可变时使用`while`循环，否则使用`for`循环。 `for`循环的常见用途是数组迭代。 1
|
|||
|
|
|
|||
|
|
## 句法
|
|||
|
|
|
|||
|
|
```C#
|
|||
|
|
for ((Initial variable); (condition); (step))
|
|||
|
|
{
|
|||
|
|
(code)
|
|||
|
|
}
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
C＃for循环由三个表达式和一些代码组成。
|
|||
|
|
|
|||
|
|
## 描述
|
|||
|
|
|
|||
|
|
* _初始变量_ ：您的起始状态，例如int i = 0;
|
|||
|
|
* _条件_ ：当此条件为真时，代码将继续运行，例如i <= 5;
|
|||
|
|
* _步骤_ ：初始变量的增量或减量，例如i ++或i- = 2。
|
|||
|
|
|
|||
|
|
## 例
|
|||
|
|
|
|||
|
|
```C#
|
|||
|
|
int[] array = { 1, 2, 3, 4, 5 };
|
|||
|
|
for (int i = 0; i < array.Length; i++)
|
|||
|
|
{
|
|||
|
|
Console.WriteLine("Item on index {0} is {1}", i, array[i]);
|
|||
|
|
}
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
## 输出：
|
|||
|
|
```
|
|||
|
|
> Item on index 0 is 1
|
|||
|
|
> Item on index 1 is 2
|
|||
|
|
> Item on index 2 is 3
|
|||
|
|
> Item on index 3 is 4
|
|||
|
|
> Item on index 4 is 5
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
### 来源
|
|||
|
|
|
|||
|
|
1 https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/for
|