how to Paint non-client area in winForms transparent? .Net 4

Question

im developing a custom form and i want that the non-client area be transparent. im handling the non client area painting via message number "0x85" and this is what i have tried so far:

• Paint using the color "Color.Transparent" -> the non-client area was painted black. If I had used an image of red or black or green, it works perfectly, but transparent = black
• Created a transparent image of the size of the form and used the method "myGraphics.DrawImage("img.png")". the background remained black. If I had used an image of red or black or green, it works perfectly also...
• Not paint anything (hoping that i just would stay transparent)... not worked

Answer 1

Getting parts of a window transparent requires hardware support, a video adapter feature called layering. Use the form's TransparencyKey property. Set it to an unusual color, like Color.Fuchsia. And draw with that color to get the video adapter to omit the pixels.