Window KeyDown

Hello! In the KeyDown event of the MainWindow, i want a message box to appear when the users presses the +/- on the keyboard. So here is my code:

if e.KeyCode = Keys.OEMPlus then MsgBox("Plus")
if e.KeyCode = Keys.OEMMinus then Msgbox("Minus")

This code works great but not for the +/- from numpad too. It only works with +/- on the main keyboard. How can i make both work?

Code:

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        If e.KeyCode = Keys.Oemplus OrElse e.KeyCode = Keys.Add Then MsgBox("Plus")
        If e.KeyCode = Keys.OemMinus OrElse e.KeyCode = Keys.Subtract Then MsgBox("Minus")

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