CODE EXAMPLE FOR CSHARP

c# UserControl make background transparent

public partial class UCTransparent : UserControl
     {

         public UCTransparent()
         {
                InitializeComponent(); 
         }
         protected override CreateParams CreateParams
         {
                get
                {
                       CreateParams cp = base.CreateParams;
                       cp.ExStyle |= 0x20;
                       return cp;
                }
         }

         protected override void OnPaintBackground(PaintEventArgs e)
         {
             base.OnPaintBackground(e);
         }
      }