Create a Win Form with curved corners

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

namespace SampleFormApplication
{
public partial class Login : Form
{
[DllImport("Gdi32.dll", EntryPoint = "CreateRoundRectRgn")]
private static extern IntPtr CreateRoundRectRgn
(
int nLeftRect,
int nTopRect,
int nRightRect,
int nBottomRect,
int nWidthEllipse,
int nHeightEllipse
);

public Login()
{
InitializeComponent();
this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
Region = System.Drawing.Region.FromHrgn(CreateRoundRectRgn(0, 0, Width - 10, Height - 10, 50, 50));
}

private void button1_Click(object sender, EventArgs e)
{
this.Close();
}
}
}