public void DwmEnableBlurBehindWindowTest()
{
var wnd = new Form {
Size = new Size(50, 50), TopMost = true, ControlBox = false, FormBorderStyle = FormBorderStyle.None
};
wnd.Show();
Thread.Sleep(1000);
var bb = new DWM_BLURBEHIND(true);
var err = DwmEnableBlurBehindWindow(wnd.Handle, ref bb);
Assert.That(err.Succeeded);
Thread.Sleep(1000);
using (var g = wnd.CreateGraphics())
{
bb.SetRegion(g, new Region(new Rectangle(0, 0, 20, 20)));
err = DwmEnableBlurBehindWindow(wnd.Handle, ref bb);
Assert.That(err.Succeeded);
Thread.Sleep(1000);
}
var bb2 = new DWM_BLURBEHIND(false);
err = DwmEnableBlurBehindWindow(wnd.Handle, ref bb2);
Assert.That(err.Succeeded);
Thread.Sleep(1000);
wnd.Hide();
}
/// <summary>
/// Enable the Aero "Blur Behind" effect on a specific region of a drawing area. Background must be black.
/// </summary>
/// <param name="window">The window.</param>
/// <param name="graphics">The graphics area on which the region resides.</param>
/// <param name="region">The region within the client area to apply the blur behind.</param>
/// <param name="enabled"><c>true</c> to enable blur behind for this region, <c>false</c> to disable it.</param>
/// <param name="transitionOnMaximized"><c>true</c> if the window's colorization should transition to match the maximized windows; otherwise, <c>false</c>.</param>
public static void EnableBlurBehind(this IWin32Window window, Graphics graphics, Region region, bool enabled, bool transitionOnMaximized)
{
if (window == null)
{
throw new ArgumentNullException(nameof(window));
}
var bb = new DWM_BLURBEHIND(enabled);
if (graphics != null && region != null)
{
bb.SetRegion(graphics, region);
}
if (transitionOnMaximized)
{
bb.TransitionOnMaximized = true;
}
DwmEnableBlurBehindWindow(window.Handle, ref bb);
}