Strange PostMessage Problem

WalthamstowBoyInSydney

Hi, I'm having a strange problem trying to postmessage out of VB.NET. I have PostMessage defined as

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

The wMsg is arriving perfectly at hwnd, but wParam is always 0 and even stranger is lParam is always equal to the value that should be in wParam :confused: :confused: The wParam is defined as a long and has the value 10 when posting, lParam is defiend as Long and has the value Me.Handle.ToInt64() When the message arrives, though wParam = 0 and lParam = 10 Any ideas? This is driving me mad! Many thanks in advance Mark

Richard Deeming

In VB6, Long was a 32-bit integer. In VB.NET, Long is a 64-bit integer, and Integer is the 32-bit integer. Unless you're working on a 64-bit version of Windows, you need to use 32-bit integers:

Public Declare Function PostMessage _
Lib "user32" _
Alias "PostMessageA" _
(ByVal hwnd As IntPtr, _
ByVal wMsg As Integer, _
ByVal wParam As Integer, _
ByVal lParam As Integer) As Integer

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