about textbox(編號:1478)

本人想限制輸入的數為XXXk or XXXM 但不能為其他
雖然以下program 能避免入其他,但不能避免入2個k or M
有乜方法改善???
Private Sub Text1_KeyPress(KeyAscii As Integer)
If KeyAscii <> 8 And KeyAscii <> 13 And KeyAscii <> 9 And KeyAscii <> 27 Then
Select Case Chr(KeyAscii)
      Case "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", ".", "k"
      Case Else
        respone = MsgBox("Please enter a number !", 48, "CAUTION")
        KeyAscii = 0
    End Select
  End If

End Sub