调用未定义的方法 PDO::execute()

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

请告诉我这里的错误

<?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"];
        }
    }

}
?>

推荐答案

->execute() 用于准备好的语句.例如

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

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