php实现数组按指定KEY排序的方法

function array_sort($arr,$keys,$orderby='asc'){
  $keysvalue = $new_array = array();
  foreach ($arr as $k=>$v){
    $keysvalue[$k] = $v[$keys];
  }
  if($orderby== 'asc'){
    asort($keysvalue);
  }else{
    arsort($keysvalue);
  }
  reset($keysvalue);
  foreach ($keysvalue as $k=>$v){
    $new_array[] = $arr[$k];
  }
  return $new_array;
}