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C if 关键字

❮ C 关键字


示例

测试两个值以找出 20 是否大于 18。如果条件为 true,则打印一些文本

int time = 20;
if (time < 18) {
  printf("Good day.");
} else {
  printf("Good evening.");
}
// 输出 "Good evening."
自己尝试 »

定义和用法

如果条件为 true,则 if 语句指定要执行的代码块。

C 具有以下条件语句

  • 使用 if 指定要执行的代码块,如果指定的条件为真
  • 使用 else 指定要执行的代码块,如果相同的条件为假
  • 使用 else if 指定一个新的条件进行测试,如果第一个条件为假
  • 使用 switch 指定要执行的许多备选代码块

更多示例

示例

使用 if 语句测试变量

int x = 20;
int y = 18;
if (x > y) {
  printf("x is greater than y");
}
自己尝试 »

相关页面

在我们的 C If...Else 教程 中了解更多关于 if 语句的信息。


❮ C 关键字

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