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HomeBackend DevelopmentPHP Tutorialphp 中switch语法的问题?

<code>switch ($para1) {
            case 1:
                return self::otherFunction($para2);
                break;
        }</code>

例子中,如果满足case 1,那么最后的break还需要吗?

回复内容:

<code>switch ($para1) {
            case 1:
                return self::otherFunction($para2);
                break;
        }</code>

例子中,如果满足case 1,那么最后的break还需要吗?

不需要了,如果在case 中使用 return 作为结束,break就是不必要的了。

有return肯定不需要下面的break了

按照楼主的写法,break就不需要了,因为程序在return时候跳转,后面的代码都不会被执行了,所以break有没有一点关系都没有。

从题注的代码上看,break是不需要的,因为return后续的代码已经不会执行了。

加上break永远不会错,不加break有时候会出错。推荐不管什么情况都加上break,这样一起工作的其他小伙伴也能更好的理解代码。

如果你只有一个选项,当然不需要,如果后面还有其他的case选项,是需要的,不然的话程序会顺序执行到下面一个选项,直到遇到一个break或结束,有时也会应用这种特性来处理多个选项一样处理方式的情况,即多个情况下不写处理方式和break,只在最后一个case内添加处理方式。
评论不会贴代码,我修改一下:如下例:

<code>switch( $i )
{
   case 1:
   case 2:
   case 3:
       $c =555;
       break;
   default:
       $c =2;
}</code>

你可以试一下这个例子~

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