public static void CreateRegion(IntPtr hWnd, int radius, RoundStyle roundStyle, bool redraw)
{
var lpRect = new RECT();
NativeMethods.GetWindowRect(hWnd, ref lpRect);
var rect = new Rectangle(Point.Empty, lpRect.Size);
if (roundStyle != RoundStyle.None)
{
using (var path = DrawHelper.CreateRoundPath(rect, radius, roundStyle, true)) //
{
using (var region = new Region(path))
{
path.Widen(Pens.White);
region.Union(path);
var windowDC = NativeMethods.GetWindowDC(hWnd);
try
{
using (var graphics = Graphics.FromHdc(windowDC))
{
NativeMethods.SetWindowRgn(hWnd, region.GetHrgn(graphics), redraw);
}
}
finally
{
NativeMethods.ReleaseDC(hWnd, windowDC);
}
}
return;
}
}
var hRgn = NativeMethods.CreateRectRgn(0, 0, rect.Width, rect.Height);
NativeMethods.SetWindowRgn(hWnd, hRgn, redraw);
}