Something has to catch the keystroke. You could create a sub or function that takes an arguement of a key and evaluates it that way. For example:

Private Sub Form_KeyPress(KeyAscii As Integer)
If IsEscapeKey(KeyAscii) Then
MsgBox "escape key"
Else
MsgBox "not escape Key"
End If
End Sub

Public Function IsEscapeKey(MyKey As Integer) As Boolean
If MyKey = vbKeyEscape Then
IsEscapeKey = True
Else
IsEscapeKey = False
End If
End Function