php自定义排序uasort函数示例【二维数组按指定键值排序】

/*
 * 二维数组按指定键值排须
 */
function arr_sort($array,$key,$order="asc"){//asc是升序 desc是降序//按 i<l<m<h 排序
  $arr_nums=$arr=array();
  foreach($array as $k=>$v){
    $arr_nums[$k]=$v[$key];
  }
  if($order=='asc'){
    uasort($arr_nums,'my_sort_asc');
  }else{
    uasort($arr_nums,'my_sort_desc');
  }
  foreach($arr_nums as $k=>$v){
    $arr[$k]=$array[$k];
  }
  return $arr;
}
function my_sort_desc($a,$b){
  if($a==$b) return 0;
  if($a=='i' && $b!='i') return 1;
  if($a=='l' && $b!='i') return 1;
  if($a=='l' && $b=='i') return -1;
  if($a=='m' && $b!='h') return -1;
  if($a=='m' && $b=='h') return 1;
  if($a=='h' && $b!='h') return -1;
}
function my_sort_asc($a,$b){
  if($a==$b) return 0;
  if($a=='i' && $b!='i') return -1;
  if($a=='l' && $b!='i') return -1;
  if($a=='l' && $b=='i') return 1;
  if($a=='m' && $b!='h') return 1;
  if($a=='m' && $b=='h') return -1;
  if($a=='h' && $b!='h') return 1;
}