php - Call to undefined method PDO::execute()

Question

i'm trying to code a page login but i was stopper at this error

pliz tell me the wrong thing here

<?php
@session_start();
include("../../connexion/connexion.php");
class login_class {
        public $user;
        public $password;
        public $connexion;
    public function check_login() {
        try {
            $cn = new class_connect();
            $this->connexion = $cn->connect(null);
            $result = $this->connexion->execute("select * from user where username='$this->user' and password='$this->password'");

                        $data = $result->fetchAll(PDO::FETCH_OBJ);


            if (!empty($data[0]->id_user)) {
                return true;
            }else {
                return false;
            }
        }catch(PDOException $ex) {  
            echo $ex->getMessage();
        }
    }
    public function __construct($user) {
        if($user){
            $this->user = $user["username"];
            $this->password = $user["password"];
        }
    }

}
?>

Answer 1

->execute() is for prepared statements. e.g.

$stmt = $dbh->prepare('some query here');
$stmt->execute();

You're trying to execute a query directly on the main DB object. For PDO, that means

 $dbh->exec('query goes here');

You really should look into prepared statements. You're vulnerable to SQL injection attacks as is, and since you're using PDO to begin with, it's basically unforgivable to NOT be writing safe queries.