PostMessage and Combobox

[Guest]

In my ComboBox, I am trying to post the CBN_EDITCHANGE message after the
CBN_SELCHANGE is received, but I am having no luck. I can trap for the
CBN_SELCHANGE message, but I cannot post the CBN_EDITCHANGE message. I think
my PostMessage parameters are wrong, but I cannot find what they should be.
Any help would be greatly appreciated. Thanks.

Here is my code. I am using VS 2003 and Visual Basic.

Private Declare Function PostMessage Lib "user32" Alias "PostMessageA" _
(ByVal hwnd As Long, _
ByVal wMsg As Long, _
ByVal wParam As Long, _
ByVal lParam As Long) As Long


Protected Overrides Sub WndProc(ByRef m As Message)
MyBase.WndProc(m)

Const CBN_SELCHANGE As Int32 = &H1
Const CBN_EDITCHANGE As Int32 = &H5
Const CBN_EDITUPDATE As Int32 = &H6
Const CBN_CLOSEUP As Int32 = &H8
Const CBN_SELENDOK As Int32 = &H9
Const WM_COMMAND As Int32 = &H111
Const WM_USER As Int32 = &H400
Const OCM__BASE As Int32 = WM_USER + &H1C00
Const OCM_COMMAND As Int32 = OCM__BASE + WM_COMMAND

If m.Msg = OCM_COMMAND Then
Dim CbAction As Int32 = (m.WParam.ToInt32 >> 16) ' combobox
action
Select Case CbAction
Case CBN_SELCHANGE
PostMessage(Me.Handle.ToInt32, OCM_COMMAND,
CBN_EDITCHANGE << 16, 0)
Case CBN_EDITCHANGE
Case CBN_CLOSEUP
Case CBN_SELENDOK
End Select
End If
End Sub

 

[Armin Zingler]

In my ComboBox, I am trying to post the CBN_EDITCHANGE message after
the CBN_SELCHANGE is received, but I am having no luck. I can trap
for the CBN_SELCHANGE message, but I cannot post the CBN_EDITCHANGE
message. I think my PostMessage parameters are wrong, but I cannot
find what they should be. Any help would be greatly appreciated.
Thanks.

Here is my code. I am using VS 2003 and Visual Basic.

Private Declare Function PostMessage Lib "user32" Alias
"PostMessageA" _
(ByVal hwnd As Long, _
ByVal wMsg As Long, _
ByVal wParam As Long, _
ByVal lParam As Long) As Long

I didn't check the code (if there's a .Net way to do it) but the declaration
is for previous VB versions. Use this one instead:

Private Declare Function PostMessage Lib "user32" Alias
"PostMessageA" _
(ByVal hwnd As intptr, _
ByVal wMsg As integer, _
ByVal wParam As integer, _
ByVal lParam As integer) As boolean



Armin

 

[Guest]

Searching the 'net, my declaration is correct VB .NET. All the params need
to be declared as Long not Integer. I still need help getting the parameter
values.

 

[Armin Zingler]

Searching the 'net, my declaration is correct VB .NET. All the
params need to be declared as Long not Integer.

No.

You may also declare wparam and lparam as IntPtr. See
System.Windows.Forms.Message.


Armin