php中的动态变量的一个应用

原文：https://www.cnblogs.com/JimmyBright/p/9869168.html

某些情况下，可以代替switch语句，大大简化代码，非常有意思哦

 $list = [
     [
         'type'=>'a',
         'name'=>'jimmy0',
         'sex'=>'mail'
     ],
     [
         'type'=>'b',
         'name'=>'jimmy1',
         'sex'=>'femail'
     ],
     [
         'type'=>'c',
         'name'=>'jimmy2',
         'sex'=>'mail'
     ],
     [
         'type'=>'a',
         'name'=>'jimmy3',
         'sex'=>'femail'
     ],
     [
         'type'=>'b',
         'name'=>'jimmy4',
         'sex'=>'femail'
     ],
     [
         'type'=>'a',
         'name'=>'jimmy5',
         'sex'=>'femail'
     ]
 ];
 $aList = [];
 $bList = [];
 $cList = [];
 foreach ($list as $item) {
     $v = $item['type'].'List';
     $$v = array_merge($$v,[$item]);//一般的做法就是在这里用switch语句了，这边就不需要了，一行代码搞定
 }
 var_export($aList);
 echo PHP_EOL;echo PHP_EOL;
 var_export($bList);
 echo PHP_EOL;echo PHP_EOL;
 var_export($cList);
 echo PHP_EOL;echo PHP_EOL;
 exit;

看一下输出：

 array (
   0 =>
   array (
     'type' => 'a',
     'name' => 'jimmy0',
     'sex' => 'mail',
   ),
   1 =>
   array (
     'type' => 'a',
     'name' => 'jimmy3',
     'sex' => 'femail',
   ),
   2 =>
   array (
     'type' => 'a',
     'name' => 'jimmy5',
     'sex' => 'femail',
   ),
 )

 array (
   0 =>
   array (
     'type' => 'b',
     'name' => 'jimmy1',
     'sex' => 'femail',
   ),
   1 =>
   array (
     'type' => 'b',
     'name' => 'jimmy4',
     'sex' => 'femail',
   ),
 )

 array (
   0 =>
   array (
     'type' => 'c',
     'name' => 'jimmy2',
     'sex' => 'mail',
   ),
 )

 Process finished with exit code 0

输出