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HomeBackend DevelopmentPHP Tutorialphp 流程控制switch的简单实例_php实例

switch允许对一个标量(表达式)的多个可能结果做选择。

语法:

switch (expr) { 
  case result1: 
  statement1 
  break; 
  case result2: 
  statement2 
  break; 
  …… 
  default: 
  statement 
} 

系统计算expr的值,根据计算结果(result1、result2等)来选择下面对应执行语句,如果所有的case结果都不符合,则会执行default里的语句。

例子:

<&#63;php 
switch ($x) { 
  case 0: 
  echo "x 等于 0"; 
  break; 
  case 1: 
  echo "x 等于 1"; 
  break; 
  case 2: 
  echo "x 等于 2"; 
  break; 
  default: 
  echo "x 既不等于1和2,也不等于0"; 
} 
&#63;> 

提示

•可以有多个 case 条件判断

•case 后面结果也不是仅限于数字,也可以是字符或其他 PHP 支持的类型

•default 不是必须的

以上这篇php 流程控制switch的简单实例就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持脚本之家。

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