how to fix Call to undefined function mysqli_connect()

Hi, I am a PHP newbie, I try invoke stored procedure in  php5, but need use mysqli_connect connect to mysql server.

when i use the connection method,it show me a error message is "Call to undefined function mysqli_connect() ",i don't know how to fix the error because I do not use php with mysql ever, but i found a solution from mysql forum:

1.click the start menu,point to run menu item then click;

2.type \windows\php.ini;

3.use "extension=php_mysqli.dll" as keyword to search in editor, if you can't get any result, please add the keyword content to the "Windows Extensions" session.

4.don't forget to restart apache.

run your application again,now. hoping  your error has fixed!