Question

I am trying to use mysqli and it has been giving me an error even though I have been
trying to fix it for hours.

this is the database class

class db {

    public $mysqli;

    function __construct(){
        $mysqli = new mysqli('host', 'user', 'password', 'database');
    }

    function clean($string){
        $string = $mysqli->real_escape_string($string);
    }

}

and when I try to call it in a test page like so,

$db = new db();
$db->clean("hi");

I get an error:

Notice: Undefined variable: mysqli in C:\xampp\htdocs\eat\class\db.class.php on line 12

Fatal error: Call to a member function real_escape_string() on a non-object in C:\xampp\htdocs\eat\class\db.class.php on line 12

is there something that I did wrong here? I have been scouring the php manual for a long time and on stackoverflow but it really seems like nobody else is facing this error.

Answer 1

You are using the variable $mysqli in the method scope. You should use $this to access object scope.

class db {

    public $mysqli;

    function __construct(){
        $this->mysqli = new mysqli('host', 'user', 'password', 'database');
    }

    function clean($string){
        return $this->mysqli->real_escape_string($string);
    }

}