Private Declare Function GetDC Lib "user32" Alias _
        "GetDC" (ByVal hwnd As Integer) As IntPtr
 
Private Declare Function ReleaseDC Lib "user32" Alias _
        "ReleaseDC" (ByVal hwnd As Integer, ByVal hdc _
        As IntPtr) As Integer
 
Private Sub Button1_Click(ByVal sender As System.Object, _
          ByVal e As System.EventArgs) Handles Button1.Click
Dim dc As IntPtr
Dim g As Graphics
Dim bla As System.Drawing.Rectangle
dc = GetDC(0)
g = Graphics.FromHdc(dc)
bla.Height = screen.PrimaryScreen.Bounds.Height
bla.Width = screen.PrimaryScreen.Bounds.Width
g.FillRectangle(Brushes.Black, bla)
g.DrawRectangle(Pens.Black, bla)
g.Dispose()
ReleaseDC(0, dc)