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:
<?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"; } ?>
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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