GDI+ Question

Does anyone know how to draw on the desktop?  Not on a form.  Let's say for example, how would you draw the following line?

Start the line at the form's left edge (y-axis doesn't matter) and draw the line to the left (in other words, off the form and across the desktop).

Please help.

Thanks in advance.
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jrandallsextonAsked:
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RonaldBiemansConnect With a Mentor Commented:
Hi jrandallsexton,

You could try one of these things,

1. With API

Declare Function GetDC Lib "user32" Alias "GetDC" (ByVal hwnd As IntPtr) As IntPtr
        Dim deskDC As IntPtr = GetDC(IntPtr.Zero)
        Dim g As Graphics = Graphics.FromHdc(deskDC)
        g.DrawLine(New Pen(Color.Black), 0, 0, 300, 300)

2. With the Controlpaint class

        Dim p1 As New Point(0, 0)
        Dim p2 As New Point(300, 300)
        ControlPaint.DrawReversibleLine(p1, p2, Color.Black)

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jrandallsextonAuthor Commented:
I haven't tried #1 but #2 works.  I've never heard of ControlPaint.  I'm going to do some reading (a lot actually) on that.

I think you've pointed me in exactly the direction I needed.  Thanks.
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RonaldBiemansCommented:
Hi Jrandallsexton,

Its a very cool class you can draw entire datagrids with that, if you combine method 1 and 2, you can even do that on the desktop.

Sorry I forgot one thing for the first method don't forget to release the dc aswell, otherwise you will run out of memory.

Declare Function ReleaseDC Lib "user32" Alias "ReleaseDC" (ByVal hwnd As Long, ByVal hdc As Long) As intptr
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