php调用mysql数据 dbclass类

$db->insert("insert into user (userid,username,password) values (null,'$username','$password')");
*/
function insert($sql){
return $this->query($sql);
}

function getid(){ //这个函数用于取得刚插入行的id
return mysql_insert_id();
}

function num_rows($query) {
$query = mysql_num_rows($query);
return $query;
}

function num_fields($query) {
return mysql_num_fields($query);
}

function free_result($query) {
return mysql_free_result($query);
}

function version() {
return mysql_get_server_info();
}

function close() {
return mysql_close();
}

function halt($message = '') {
return $message;
}
}

$db=new dbClass("$db_username","$db_password","$db_database","$db_hostname");
$db->connect();
$db->select();