/// <summary> /// Captures a screenshot of the specified window at the specified /// bitmap size. <para/>NOTE: This method will not accurately capture controls /// that are hidden or obstructed (partially or completely) by another control (e.g. hidden tabs, /// or MDI child windows that are obstructed by other child windows/forms). /// </summary> /// <param name="windowHandle">The window handle.</param> /// <param name="bitmapSize">The requested bitmap size.</param> /// <returns>A screen capture of the window.</returns> public static Bitmap GrabWindowBitmap(IntPtr windowHandle, System.Drawing.Size bitmapSize) { if (bitmapSize.Height <= 0 || bitmapSize.Width <= 0) { return(null); } IntPtr windowDC = IntPtr.Zero; try { windowDC = HandlerNativeMethods.GetWindowDC(windowHandle); _ = HandlerNativeMethods.GetClientSize(windowHandle, out System.Drawing.Size realWindowSize); if (realWindowSize == System.Drawing.Size.Empty) { realWindowSize = new System.Drawing.Size(200, 200); } System.Drawing.Size size = (bitmapSize == System.Drawing.Size.Empty) ? realWindowSize : bitmapSize; Bitmap targetBitmap = null; try { targetBitmap = new Bitmap(size.Width, size.Height); using (var targetGr = Graphics.FromImage(targetBitmap)) { IntPtr targetDC = targetGr.GetHdc(); uint operation = 0x00CC0020 /*SRCCOPY*/; System.Drawing.Size ncArea = Shell.DesktopWindowManager.GetNonClientArea(windowHandle); bool success = GDI.StretchBlt( targetDC, 0, 0, targetBitmap.Width, targetBitmap.Height, windowDC, ncArea.Width, ncArea.Height, realWindowSize.Width, realWindowSize.Height, operation); targetGr.ReleaseHdc(targetDC); return(success ? targetBitmap : null); } } catch { targetBitmap?.Dispose(); throw; } } finally { if (windowDC != IntPtr.Zero) { _ = HandlerNativeMethods.ReleaseDC(windowHandle, windowDC); } } }
private static bool DispatchLivePreviewBitmapMessage(ref System.Windows.Forms.Message m, TaskbarWindow taskbarWindow) { if (m.Msg == (int)WindowMessage.DWMSendIconicLivePreviewBitmap) { // Try to get the width/height int width = (int)(((long)m.LParam) >> 16); int height = (int)(((long)m.LParam) & (0xFFFF)); // Default size for the thumbnail var realWindowSize = new System.Drawing.Size(200, 200); if (taskbarWindow.TabbedThumbnail.WindowHandle != IntPtr.Zero) _ = HandlerNativeMethods.GetClientSize(taskbarWindow.TabbedThumbnail.WindowHandle, out realWindowSize); else if (taskbarWindow.TabbedThumbnail.WindowsControl != null) realWindowSize = new System.Drawing.Size( Convert.ToInt32(taskbarWindow.TabbedThumbnail.WindowsControl.RenderSize.Width), Convert.ToInt32(taskbarWindow.TabbedThumbnail.WindowsControl.RenderSize.Height)); // If we don't have a valid height/width, use the original window's size if (width <= 0) width = realWindowSize.Width; if (height <= 0) height = realWindowSize.Height; // Fire an event to let the user update their bitmap // Raise the event taskbarWindow.TabbedThumbnail.OnTabbedThumbnailBitmapRequested(); // capture the bitmap for the given control // If the user has already specified us a bitmap to use, use that. IntPtr hBitmap = taskbarWindow.TabbedThumbnail.CurrentHBitmap == IntPtr.Zero ? GrabBitmap(taskbarWindow, realWindowSize) : taskbarWindow.TabbedThumbnail.CurrentHBitmap; // If we have a valid parent window handle, // calculate the offset so we can place the "peek" bitmap // correctly on the app window if (taskbarWindow.TabbedThumbnail.ParentWindowHandle != IntPtr.Zero && taskbarWindow.TabbedThumbnail.WindowHandle != IntPtr.Zero) { // if we don't have a offset specified already by the user... Point offset = !taskbarWindow.TabbedThumbnail.PeekOffset.HasValue ? Shell.DesktopWindowManager.GetParentOffsetOfChild(taskbarWindow.TabbedThumbnail.WindowHandle, taskbarWindow.TabbedThumbnail.ParentWindowHandle) : new Point(Convert.ToInt32(taskbarWindow.TabbedThumbnail.PeekOffset.Value.X), Convert.ToInt32(taskbarWindow.TabbedThumbnail.PeekOffset.Value.Y)); // Only set the peek bitmap if it's not null. // If it's null (either we didn't get the bitmap or size was 0), // let DWM handle it if (hBitmap != IntPtr.Zero && offset.X >= 0 && offset.Y >= 0) DesktopWindowManager.SetPeekBitmap( taskbarWindow.WindowToTellTaskbarAbout, hBitmap, offset, taskbarWindow.TabbedThumbnail.DisplayFrameAroundBitmap); // If the bitmap we have is not coming from the user (i.e. we created it here), // then make sure we delete it as we don't need it now. if (taskbarWindow.TabbedThumbnail.CurrentHBitmap == IntPtr.Zero) _ = GDI.DeleteObject(hBitmap); return true; } // Else, we don't have a valid window handle from the user. This is mostly likely because // we have a WPF UIElement control. If that's the case, use a different screen capture method // and also couple of ways to try to calculate the control's offset w.r.t it's parent. else if (taskbarWindow.TabbedThumbnail.ParentWindowHandle != IntPtr.Zero && taskbarWindow.TabbedThumbnail.WindowsControl != null) { System.Windows.Point offset; if (!taskbarWindow.TabbedThumbnail.PeekOffset.HasValue) { // Calculate the offset for a WPF UIElement control // For hidden controls, we can't seem to perform the transform. GeneralTransform objGeneralTransform = taskbarWindow.TabbedThumbnail.WindowsControl.TransformToVisual(taskbarWindow.TabbedThumbnail.WindowsControlParentWindow); offset = objGeneralTransform.Transform(new System.Windows.Point(0, 0)); } else offset = new System.Windows.Point(taskbarWindow.TabbedThumbnail.PeekOffset.Value.X, taskbarWindow.TabbedThumbnail.PeekOffset.Value.Y); // Only set the peek bitmap if it's not null. // If it's null (either we didn't get the bitmap or size was 0), // let DWM handle it if (hBitmap != IntPtr.Zero) if (offset.X >= 0 && offset.Y >= 0) DesktopWindowManager.SetPeekBitmap( taskbarWindow.WindowToTellTaskbarAbout, hBitmap, new Point((int)offset.X, (int)offset.Y), taskbarWindow.TabbedThumbnail.DisplayFrameAroundBitmap); else DesktopWindowManager.SetPeekBitmap( taskbarWindow.WindowToTellTaskbarAbout, hBitmap, taskbarWindow.TabbedThumbnail.DisplayFrameAroundBitmap); // If the bitmap we have is not coming from the user (i.e. we created it here), // then make sure we delete it as we don't need it now. if (taskbarWindow.TabbedThumbnail.CurrentHBitmap == IntPtr.Zero) _ = GDI.DeleteObject(hBitmap); return true; } else { // Else (no parent specified), just set the bitmap. It would take over the entire // application window (would work only if you are a MDI app) // Only set the peek bitmap if it's not null. // If it's null (either we didn't get the bitmap or size was 0), // let DWM handle it if (hBitmap != null) DesktopWindowManager.SetPeekBitmap(taskbarWindow.WindowToTellTaskbarAbout, hBitmap, taskbarWindow.TabbedThumbnail.DisplayFrameAroundBitmap); // If the bitmap we have is not coming from the user (i.e. we created it here), // then make sure we delete it as we don't need it now. if (taskbarWindow.TabbedThumbnail.CurrentHBitmap == IntPtr.Zero) _ = GDI.DeleteObject(hBitmap); return true; } } return false; }
private static bool DispatchSendIconThumbnailMessage(ref System.Windows.Forms.Message m, TaskbarWindow taskbarWindow) { if (m.Msg == (int)WindowMessage.DWMSendIconicThumbnail) { int width = (int)((long)m.LParam >> 16); int height = (int)(((long)m.LParam) & (0xFFFF)); var requestedSize = new System.Drawing.Size(width, height); // Fire an event to let the user update their bitmap taskbarWindow.TabbedThumbnail.OnTabbedThumbnailBitmapRequested(); IntPtr hBitmap; // Default size for the thumbnail var realWindowSize = new System.Drawing.Size(200, 200); // Get the size of teh control or UIElement if (taskbarWindow.TabbedThumbnail.WindowHandle != IntPtr.Zero) _ = HandlerNativeMethods.GetClientSize(taskbarWindow.TabbedThumbnail.WindowHandle, out realWindowSize); else if (taskbarWindow.TabbedThumbnail.WindowsControl != null) realWindowSize = new System.Drawing.Size( Convert.ToInt32(taskbarWindow.TabbedThumbnail.WindowsControl.RenderSize.Width), Convert.ToInt32(taskbarWindow.TabbedThumbnail.WindowsControl.RenderSize.Height)); if (realWindowSize.Height == -1 && realWindowSize.Width == -1) realWindowSize.Width = realWindowSize.Height = 199; // capture the bitmap for the given control // If the user has already specified us a bitmap to use, use that. if (taskbarWindow.TabbedThumbnail.ClippingRectangle != null && taskbarWindow.TabbedThumbnail.ClippingRectangle.Value != Rectangle.Empty) { hBitmap = taskbarWindow.TabbedThumbnail.CurrentHBitmap == IntPtr.Zero ? GrabBitmap(taskbarWindow, realWindowSize) : taskbarWindow.TabbedThumbnail.CurrentHBitmap; // Clip the bitmap we just got. Bitmap bmp = Image.FromHbitmap(hBitmap); Rectangle clippingRectangle = taskbarWindow.TabbedThumbnail.ClippingRectangle.Value; // If our clipping rect is out of bounds, update it if (clippingRectangle.Height > requestedSize.Height) clippingRectangle.Height = requestedSize.Height; if (clippingRectangle.Width > requestedSize.Width) clippingRectangle.Width = requestedSize.Width; // NOTE: Is this a memory leak? bmp = bmp.Clone(clippingRectangle, bmp.PixelFormat); // Make sure we dispose the bitmap before assigning, otherwise we'll have a memory leak if (hBitmap != IntPtr.Zero && taskbarWindow.TabbedThumbnail.CurrentHBitmap == IntPtr.Zero) _ = GDI.DeleteObject(hBitmap); hBitmap = bmp.GetHbitmap(); bmp.Dispose(); } else { // Else, user didn't want any clipping, if they haven't provided us a bitmap, // use the screencapture utility and capture it. hBitmap = taskbarWindow.TabbedThumbnail.CurrentHBitmap; // If no bitmap, capture one using the utility if (hBitmap == IntPtr.Zero) hBitmap = GrabBitmap(taskbarWindow, realWindowSize); } // Only set the thumbnail if it's not null. // If it's null (either we didn't get the bitmap or size was 0), // let DWM handle it if (hBitmap != IntPtr.Zero) { Bitmap temp = TabbedThumbnailScreenCapture.ResizeImageWithAspect( hBitmap, requestedSize.Width, requestedSize.Height, true); if (taskbarWindow.TabbedThumbnail.CurrentHBitmap == IntPtr.Zero) _ = GDI.DeleteObject(hBitmap); hBitmap = temp.GetHbitmap(); DesktopWindowManager.SetIconicThumbnail(taskbarWindow.WindowToTellTaskbarAbout, hBitmap); temp.Dispose(); } // If the bitmap we have is not coming from the user (i.e. we created it here), // then make sure we delete it as we don't need it now. if (taskbarWindow.TabbedThumbnail.CurrentHBitmap == IntPtr.Zero) _ = GDI.DeleteObject(hBitmap); return true; } return false; }