请问mysqli_select_db() expects parameter 1 to be mysqli

$conn=@ mysqli_connect('localhost' ,'root' ,'888888','')or die ('出错');
mysqli_select_db('bbs',$conn);
mysqli_query("set names 'gbk'");



Warning: mysqli_select_db() expects parameter 1 to be mysqli, string given in C:\wamp\www\ty\db.php on line 10

Warning: mysqli_query() expects at least 2 parameters, 1 given in C:\wamp\www\ty\db.php on line 11

bool mysqli_select_db ( mysqli $link , string $dbname )

写反了.或者

bool mysqli::select_db ( string $dbname )

bool mysqli_select_db ( mysqli link, string dbname )
写错位置了