Вычисление значений функции двух переменных в Visual Basic - Visual Basic - VB

Private Sub Command1_Click()
    Dim R As Double, X As Double, Y As Double
    If Text1.Text = "" Or Text2.Text = "" Then MsgBox "Введите данные во все поля": Exit Sub
    X = VR(Text1.Text)
    Y = VR(Text2.Text)
    If Y * Sqr(X + 1) = 0 Or (Y + 1) <= 0 Then '
       Text3.Text = "Ошибка!"
    Else
       R = (X * Log(Y + 1) - 2) / (Y * Sqr(X + 1))
       Text3.Text = Round(R, 4)
    End If
End Sub
 
Private Sub Command2_Click()
    Text1.Text = ""
    Text2.Text = ""
    Text3.Text = ""
End Sub
 
Function VR(ByVal s As String) As Double
    VR = Val(Replace(s, ",", "."))
End Function