/// <summary>
/// In some circumstances, the window manager will draw the window larger than it reports
/// its size to be. You can use this function to retrieve the size of this extra border
/// padding.
/// </summary>
/// <param name="window"></param>
/// <returns>
/// An integer greater than or equal to zero that describes the size of the border padding
/// which is not reported via the window's Size or Bounds property.
/// </returns>
/// <remarks>
/// Note to implementors: This method may simply return 0. It is provided for use in Windows
/// Vista when DWM+Aero is enabled in which case sizable FloatingToolForm windows do not
/// visibly dock to the correct locations.
/// </remarks>
public static int GetExtendedFrameBounds(Form window)
{
int returnVal;
if (OS.IsVistaOrLater)
{
unsafe
{
int *rcVal = stackalloc int[4];
int hr = SafeNativeMethods.DwmGetWindowAttribute(
window.Handle,
NativeConstants.DWMWA_EXTENDED_FRAME_BOUNDS,
(void *)rcVal,
4 * (uint)sizeof(int));
if (hr >= 0)
{
returnVal = -rcVal[0];
}
else
{
returnVal = 0;
}
}
}
else
{
returnVal = 0;
}
GC.KeepAlive(window);
return(Math.Max(0, returnVal));
}
