PHP 多层循环 如何跳出循环？

1.跳出内循环

在内循环里使用break只会跳出单层循环，并不会影响外层循环工作。

	function test2()
    {
    
    
        $a = [1,2,3,5,6,7,8,9];
        $b = [3,5,6,7,10,8];

       foreach ($a as $value){
    
    
           foreach ($b as $v){
    
    
               if($value == $v){
    
    
                 var_dump($v); // 会输出：3、5、6、7、8
                  break;
               }
           }
           echo $value;  //12356789
       }
    }
  

1.跳出内循环继续外循环

在循环内 continue或break 后加数字可以指定跳出几层循环，比如 continue 2; 就是跳出2层循环

  
    function test2()
    {
    
    
        $a = [1,2,3,5,6,7,8,9];
        $b = [3,5,6,7,10,8];

       foreach ($a as $value){
    
    
           foreach ($b as $v){
    
    
               if($value == $v){
    
    
                   continue 2;
               }
           }
           echo $value;  //129
       }
    }
    
    function test3()
    {
    
    
        $a = [1,2,3,5,6,7,8,9];
        $b = [3,5,6,7,10,8];

       foreach ($a as $value){
    
    
           foreach ($b as $v){
    
    
               if($value == $v){
    
    
                   break 2;
               }
           }
           echo $value;  //12
       }
    }