Get a image of a control even when a control is not visible.

Question

I'm looking for a way to get the the image of a control even when it is not visible in screen (for example when the form is minimized or the control is under another control). This clasical way to capture screen image is not good : Graphics g1 = myControl.CreateGraphics(); Image myImage = new Bitmap(myControl.Width myControl.Height g1); Graphics g2 = Graphics.FromImage(myImage); IntPtr dc1 = g1.GetHdc(); IntPtr dc2 = g2.GetHdc(); BitBlt(dc2 0 0 myControl.Width myControl.Height dc1 0 0 13369376); g1.ReleaseHdc(dc1); g2.ReleaseHdc(dc2); myImage.Save(c:\Captured.jpg ImageFormat.Jpeg); Any idea?? Thanks Daniel

psy4fun · Answer

Try to use GDI+. Create a new class inherits the control and add the following method to the new class: public Bitmap GetBitmap() { Bitmap b = new Bitmap(this.ClientRectangle.Width this.ClientRectangle.Height); Graphics g = Graphics.FromImage(b); PaintEventArgs pe = new PaintEventArgs(gthis.ClientRectangle); base.OnPaint(pe); return b; }

Tati08 · Answer

Hi Daniel I would also be interested in this isue. I want to keep updating the control even if it is not visible or at least save the last controlimage before miminized by the user. I think one of the ways is to use BitBlt but I have no idea how to give the parameters of the control I want to capture. [DllImport(gdi32.dllEntryPoint=BitBlt)] public static extern bool BitBlt(IntPtr hdcDestint xDest int yDestint wDestint hDestIntPtr hdcSource int xSrcint ySrcint RasterOp); If you found out the solution by now please let me know too. Tati