Procedure Not Increasing Correctly 3

[quest4]

Good afternoon. I have a OnKeyDown event procedure, which when CTRL-b is pressed It increase the value of PartGroup by one. It is not increasing it at all. Can someone please look at this code and tell me what I did wrong?
Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
Dim ControlDDown As Integer
ControlDDown = (KeyCode = vbKeyD And Shift And acCtrlMask) > 0

If ControlDDown = True Then
Me!PartGroup = Me!PartGroup + 1
Me!ItemNumber = Nz(DMax("[ItemNumber]", "stblECN_BOM", "[PartGroup] = " & Me!PartGroup), 0) + 1
End If
End Sub
I haven't gotten far enoughto know if it is resetting ItemNumber to to 1 yet. Thank you very much to anyone who helps straighten this out

 

[quest4]

Thank you for the reply, Tony. I did some experimenting over the weekend, I am beginning to think I shouldn't have, but here goes. Here is the code that controls the initial numbering:
Private Sub Form_BeforeInsert(Cancel As Integer)
If IsNull(Me!PartGroup) Then
Me!PartGroup = Nz(DMax("[PartGroup]", "stblECN_BOM&quot, 1)
End If
If IsNull(Me!ItemNumber) Then
Me!ItemNumber = Nz(DMax("[ItemNumber]", "stblECN_BOM", "[PartGroup] = '" & Me!PartGroup) & "'", 0) + 1
End If
End Sub
This works fine by it self, but when the code below is added, the ItemNumber code in either procedure stop function and start run-time erroring. Here is the the second part:
Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
Dim ControlBDown As Integer
ControlBDown = (KeyCode = vbKeyB And Shift And acCtrlMask) > 0
If ControlBDown = True Then
Me!PartGroup = Nz(DMax("[PartGroup]", "stblECN_BOM&quot) + 1
Me!ItemNumber = Nz(DMax("[ItemNumber]", "stblECN_BOM", "[PartGroup] = " & Me!PartGroup), 0)
End If
End Sub
The Groups appear to be working correctly, but it is hard to tell. Why is ItemNumber not working? Thank you again for your assistance.