forms C# applications

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        string Username = "ezz";
        string Password = "zezo";

        private void button1_Click(object sender, EventArgs e)
        {
            if (textBox1.Text != null && textBox1.Text == Username)
            {
                if (textBox2.Text != null && textBox2.Text == Password)
                {
                    this.Close();
                }
                else
                {
                    MessageBox.Show("wrong password");
                }
            }
        }

        private void button2_Click(object sender, System.EventArgs e)
        {
            Application.Exit();
        }

    }
}