Warning: mysqli_real_escape_string() expects exactly 2 parameters, 1 given… what i do wrong?

Question

I try make php login but i get this error: Warning: mysqli_real_escape_string() expects exactly 2 parameters, 1 given, what I do wrong?

register.php

Answer 1

you are mixing mysql and mysqli

use this mysql_real_escape_string like

$username = mysql_real_escape_string($_POST['username']);

NOTE : mysql_* is deprecated use mysqli_* or PDO