hDC in VB.Net

[theController]

does any one knwo how to get this value in Vb.Net?

and is this value large for an object in vb6?

[Jacob Roman]

Form1.DefInstance.Handle.ToInt32

Yes since you are using ToInt32

[Jacob Roman]

Shoot. My bad. It only works when VB6 Forms have been upgraded to VB.NET and have contained code on hDC's.

[Jacob Roman]

Try doing this:

Dim Form as New Control

and use Form.Handle.Int32 for whereever hDC was needed.

[Jacob Roman]

I was wrong. Handle is actually like VB6's hWnd. Sorry, but at least I tried.

[Jacob Roman]

AH HA, here it is:

Dim Form as New Form1
Dim hDC as Long

hdc = Form1.CreateGraphics.GetHdc.ToInt32

GetHdc is a hidden member and won't appear in the list after typing CreateGraphics.

[Verzulsan]

Thanks Jacob Roman from 8 years ago.
hdc = Form1.CreateGraphics.GetHdc.ToInt32 Its exactely what I needed to get the handler of my form..

[MichaelSpectre]

Just an FYI, Verzulsan from 1 month ago, there is no need to append ".ToInt32" to that since it is already an IntPtr. Also, be sure to use ".ReleaseHdc" afterwards, like so:

Dim g As Graphics = Form1.CreateGraphics()
Dim hdc As IntPtr = g.GetHdc() ' Borrows control over the device context
'
' Use the device context here...
'
g.ReleaseHdc()' Gives control back to owner

This will pass ownership of the device context back to the original owner, allowing the graphics device to continue as it normally would.

[Mikle]

A more correct version:

Imports System.Runtime.InteropServices
Public Class Form1
  Dim Grp As Graphics
  Dim hDC As HandleRef

  Private Sub Form1_HandleCreated(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.HandleCreated
    Grp = Me.CreateGraphics
    hDC = New HandleRef(Grp, Grp.GetHdc)
  End Sub

  Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
    DirectCast(hDC.Wrapper, Graphics).ReleaseHdc()
    Grp.Dispose()
  End Sub
End Class