根据二维数组的某列数值来对二维数组进行排序

function my_sort($arrays,$sort_key,$sort_order=SORT_DESC,$sort_type=SORT_NUMERIC ){  
        if(is_array($arrays)){  
            foreach ($arrays as $array){  
                if(is_array($array)){  
                    $key_arrays[] = $array[$sort_key];  
                }else{  
                    return false;  
                }  
            }  
        }else{  
            return false;  
        }
        array_multisort($key_arrays,$sort_order,$sort_type,$arrays);  
        return $arrays;  
    }