How to connect to database using php

1. <?php
3. function OpenCon()
4. {
5. $dbhost = "localhost";
6. $dbuser = "root";
7. $dbpass = "1234";
8. $db = "example";
11. $conn = new mysqli($dbhost, $dbuser, $dbpass,$db) or die("Connect failed: %s\n". $conn -> error);
14. return $conn;
15. }
17. function CloseCon($conn)
18. {
19. $conn -> close();
20. }
22. ?>