二维数组按某字段排序算法

/**
 * 二维数组按某字段排序算法
 * @param array $arrUsers 要排序的数组
 * @param string $field 排序字段
 * @param string $direction 排序顺序标志 SORT_DESC 降序；SORT_ASC 升序
 * @return array 返回排序后的数组
 * @author mosishu
 */
function array_sort($arrUsers,$field,$direction){
    if ($direction=="ASC" || $direction=="asc" || $direction=="SORT_ASC"){
        $order = "SORT_ASC";
    }elseif ($direction=="DESC" || $direction=="desc" || $direction=="SORT_DESC"){
        $order = "SORT_DESC";
    }else{
        return $arrUsers;
    }
    $sort = array(
        "direction" => $order, //排序顺序标志 SORT_DESC 降序；SORT_ASC 升序
        "field"     => $field, //排序字段
    );
    $arrSort = array();
    foreach($arrUsers AS $uniqid => $row){
        foreach($row AS $key=>$value){
            $arrSort[$key][$uniqid] = $value;
        }
    }
    if($sort["direction"]){
        array_multisort($arrSort[$sort["field"]], constant($sort["direction"]), $arrUsers);
    }
    return $arrUsers;
}