Transparent background on winforms?

Question

I wanted to make my windows form transparent so removed the borders, controls and everything leaving only the forms box, then I tried to the BackColor and TransparencyKey to

Answer 1

A simple solution to get a transparent background in a windows form is to overwrite the OnPaintBackground method like this:

protected override void OnPaintBackground(PaintEventArgs e)
{
    //empty implementation
}

(Notice that the base.OnpaintBackground(e) is removed from the function)