C# Signature:

[DllImport("user32.dll", SetLastError = true)]
static extern bool PostMessage(IntPtr hWnd, uint Msg, UIntPtr wParam,
   IntPtr lParam);

User-Defined Types:

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

Notes:

MSDN says: If the function fails, the return value is zero. To get extended error information, call GetLastError.

Tips & Tricks:

Please add some!

Sample Code:

A wrapper for PostMessage looking for errors:

    int PostMessageSafe( IntPtr hWnd, int msg, int wParam, int lParam )
    {
        int returnValue = PostMessage( hWnd, msg, wParam, lParam );

        if( returnValue == 0 )
        {
        // An error occured
        throw new Win32Exception( Marshal.GetLastWin32Error() );
        }

        return returnValue;
    }        

Alternative Managed API:

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