Fatal error: Uncaught Error: Call to undefined function mysqli_connect() in K:\zhaociyu.com\SaxueFrame\lib\database\mysqli\db.php:75 Stack trace: #0 K:\zhaociyu.com\SaxueFrame\lib\database\mysqli\db.php(187): saxuemysqlidatabase->connect(false) #1 K:\zhaociyu.com\www\lishi.php(77): saxuemysqlidatabase->query('SELECT content ...') #2 {main} thrown in K:\zhaociyu.com\SaxueFrame\lib\database\mysqli\db.php on line 75