PHP MySQLi问题显示我的记录和结果

Question

我的代码存在问题我想显示查询结果，但不能正常工作（$run_user['user_name'];部分）。

if(isset($_POST)){
    $email = $_POST['email'];
    $pass = $_POST['pass'];

    $sel_user = "SELECT * FROM users WHERE user_email='$email' AND user_password='$pass'";

    $run_user = mysqli_query($con, $sel_user);
    $check_user = mysqli_num_rows($run_user);

    if($check_user>0){
        $_SESSION["user_name"] = $run_user['user_name'];

        echo "<script>alert('logged in')</script>";
    }
    else {
        echo "<script>alert('Email or password is not correct, try again!')</script>";
    }
}