Private Declare Function SetCursorPos Lib “user32″ (ByVal x As Long, ByVal Y As Long) As Long
Private Declare Sub mouse_event Lib “user32″ (ByVal dwFlags As Long, ByVal dx As Long, ByVal dy As Long, ByVal cButtons As Long, ByVal dwExtraInfo As Long)
Private Const MOUSEEVENTF_LEFTDOWN = &H2
Private Const MOUSEEVENTF_LEFTUP = &H4

Private Sub ListBox1_MouseDown(ByVal Button As Integer, ByVal Shift As Integer, ByVal x As Single, ByVal Y As Single)
If Button = 2 Then
mouse_event MOUSEEVENTF_LEFTDOWN, 0&, 0&, 0&, 0&
mouse_event MOUSEEVENTF_LEFTUP, 0&, 0&, 0&, 0&
End If
End Sub

Like that! =]

I prefer this version it allows you to wire it to multiple listboxes.

private void listBox_MouseDown(object sender, MouseEventArgs e)
{
ListBox lst = (ListBox) sender;
// Select item if right click.
if (MouseButtons.Right == e.Button)
{
Point pt = new Point(e.X, e.Y);
lst.SelectedIndex = lst.IndexFromPoint(pt);
}
}

Generally I prefer the “SenderType foo = (SenderType) sender;” pattern as opposed to calling the item by its class member name in events.