use the KeyDown Event for the textbox, ensure you set the Form's KeyPreview Event to Yes. This Code will get you started
Private Sub Text1_KeyDown(KeyCode As Integer, Shift As Integer)
If KeyCode = 38 Then
MsgBox "UpArrow"
ElseIf KeyCode = 40 Then
MsgBox "DownArrow"
Else
MsgBox "Other Key"
End If
End Sub
PaulF