public void UseDWMThumbnail(IntPtr ipHandle, System.Windows.Forms.Form frmParent, ref IntPtr ipThumbnailRef)
{
if (frmParent != null && ipHandle != IntPtr.Zero)
{
AWC.WindowHandle.NativStructs.RECT rec = new AWC.WindowHandle.NativStructs.RECT(7, 35, 150, 120);
DWMThumbnail.Registry(frmParent, ipHandle, ref ipThumbnailRef);
DWMThumbnail.Update(ipThumbnailRef, rec);
}
}
public static void Update(IntPtr iptrThumb, AWC.WindowHandle.NativStructs.RECT _rec)
{
if (iptrThumb != IntPtr.Zero)
{
System.Drawing.Size size = new System.Drawing.Size();
Nativ.DwmQueryThumbnailSourceSize(iptrThumb, ref size);
NativStructs.ThumbnailProperties props = new NativStructs.ThumbnailProperties();
props.Visible = true;
props.TNP = NativStructs.Dwm_TNP.Visible | NativStructs.Dwm_TNP.Recdestination | NativStructs.Dwm_TNP.Opacity;
props.opacity = 255;
props.rcDestination = _rec;
if (size.Height < _rec.Height)
{
props.rcDestination.Bottom = props.rcDestination.Top + size.Height;
}
if (size.Width < _rec.Width)
{
props.rcDestination.Right = props.rcDestination.Left + size.Width;
}
//calculate scalingfor the Thumb to center it
double radio = (size.Height / _rec.Height);
int nWidth = (int)(size.Width / radio);
int nHeight = (int)(size.Height / radio);
if (nHeight > _rec.Height || nWidth < 0 || nHeight < 0)
{
radio = (size.Width / _rec.Width);
nWidth = (int)(size.Width / radio);
nHeight = (int)(size.Height / radio);
}
if (_rec.Width > nWidth)
{
props.rcDestination.Left += (_rec.Width - nWidth) / 2;
}
if (_rec.Height > nHeight)
{
props.rcDestination.Top += (_rec.Height - nHeight) / 2;
}
props.rcDestination.Width = _rec.Width;
props.rcDestination.Height = _rec.Height;
AWC.WindowHandle.Nativ.DwmUpdateThumbnailProperties(iptrThumb, ref props);
}
else
{
throw new ArgumentNullException("iptrThumb, ctrl", "Can't Update Thumbnail");
}
}
