常用的PHP工具类

StringUtil

1. 生成随机字符串

   function randomString($length = 6) :string
   {
       $pattern = '1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
       $str = '';
       for ($i = 0; $i < $length; $i++) {
           $str .= $pattern{mt_rand(0, 61)};
       }
   
       return $str;
   }

2. Get a subset of the items from the given array.

   /**
    * @param  array $array
    * @param  array|string $keys
    * @return array
    */
   function array_only($array, $keys) 
   {
       return array_intersect_key($array, array_flip((array) $keys));
   }
   # array_flip： 交换数组中的键和值