Dim FlagKeyb As Boolean

Private Sub Command1_Click()
FlagKeyb = Not FlagKeyb
If FlagKeyb Then
Command1.Caption = "Отключить"
Else
Command1.Caption = "Включить"
End If
Text1.SetFocus
End Sub

Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
If FlagKeyb Then
Else
KeyCode = 0
End If
End Sub
Private Sub Form_KeyPress(KeyAscii As Integer)
If FlagKeyb Then
Else
KeyAscii = 0
End If
End Sub
Private Sub Form_KeyUp(KeyCode As Integer, Shift As Integer)
If FlagKeyb Then
Else
KeyCode = 0
End If
End Sub

Private Sub Form_Load()
FlagKeyb = True
Command1.Caption = "Отключить"
End Sub