WinForm close the landing window, open the main form of realization

First code Solution Manager (Program.cs) in the

static void Main()  
{  
    Application.EnableVisualStyles();  
    Application.SetCompatibleTextRenderingDefault(false);  
    Form Login = new Login();  
    Login.ShowDialog();//显示登陆窗体  
    if (Login.DialogResult == DialogResult.OK)  
        Application.Run(new Main());//判断登陆成功时主进程显示主窗口  
    else return;  
}  

Then in the login window (Login.cs) login button (BTLogin) Click event in

private void BTLogin_Click(object sender, EventArgs e)  
{  
    if (TBUserName.Text == "www.520360.com" && TBPassWord.Text == "123")  
    {  
        this.DialogResult = DialogResult.OK;//关键:设置登陆成功状态  
        this.Close();  
    }  
    else  
    {  
        MessageBox.Show("账号或密码错误，请重试");  
    }  
}