Private Sub CmdCase_Click()
Select Case TxtNilai.Text
Case "a": MsgBox "sangat baik"
Case "b": MsgBox "baik"
Case "c": MsgBox "cukup"
End Select
End Sub

Private Sub CmdIf_Click()
If TxtNilai.Text = "a" Then
MsgBox "sangat baik"
ElseIf TxtNilai.Text = "b" Then
MsgBox "baik"
ElseIf TxtNilai.Text = "c" Then
MsgBox "cukup"
End If
End Sub