问如何检查两个时间戳是否在一个范围内

EN

<?php
  function check_range($time1, $time2, $max_difference)
  {
      $overlap = abs($time1-$time2);
      if($overlap < $max_difference)
      {
         return 0;
      }
      else
      {
        return $overlap;
      }

  }