55 lines
1.1 KiB
Markdown
55 lines
1.1 KiB
Markdown
---
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title: Do...While Loop
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localeTitle: 做......循环
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---
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# 做......循环
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`do while`类似于`while`循环,但是在检查给定条件之前,保证语句组至少运行一次。 需要注意的一点是'while'循环是一个退出控制循环。虽然(它不一定会执行),'do while'是一个入口控制循环(它将至少执行一次,即使条件不是真的)。
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```java
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do
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{
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// Statements
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}
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while (condition);
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```
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## 例
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```java
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int iter_DoWhile = 20;
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do
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{
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System.out.print (iter_DoWhile + " ");
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// Increment the counter
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iter_DoWhile++;
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}
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while (iter_DoWhile < 10);
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System.out.println("iter_DoWhile Value: " + iter_DoWhile);
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```
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输出:
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```
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20
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iter_DoWhile Value: 21
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```
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**记住** :执行一次代码体之后检查`do-while`循环的条件。
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![:rocket:](//forum.freecodecamp.com/images/emoji/emoji_one/rocket.png?v=2 ":火箭:") [运行代码](https://repl.it/CJYl/0)
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## 行使
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你能猜出以下代码片段的输出吗?
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```java
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int i = 10;
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do
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{
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System.out.println("The value of i is " + i);
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i--;
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}
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while (i >= 10);
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``` |