Visual Studios help guide says the maximum possible value for it to store in a decimal is 79,228,162,514,264,337,593,543,950,335 Whenever I put a large number the program does nothing at all so I wanted to display an error message for the user asking them to enter a smaller value or somehow detect an overflow. I tried using 

```
If lengtha = 79,228,162,514,264,337,593,543,950,335 Then
                MsgBox("Can not compute, try a smaller value.")
            End If

```

but it did not work out. Here is the code so far.

```
Class MainWindow 

Private Sub Button_Click(sender As Object, e As RoutedEventArgs) Handles Calculate.Click
    Dim length As String = LengthTextBox.Text
    If IsNumeric(length) Then

    Else
        MsgBox("The value entered in legnth is not numeric, please enter a numeric value.", MsgBoxStyle.OkOnly, "Error")

    End If

    Dim width As String = WidthTextBox.Text
    If IsNumeric(width) Then

    Else
        MsgBox("The value entered in width is not numeric, please enter a numeric value.", MsgBoxStyle.OkOnly, "Error")

    End If

    Try
        Dim lengtha As Decimal = Decimal.Parse(length)
        If lengtha < 0 Then
            MsgBox("Length can not be negative.")
            Return
        End If

        Dim widtha As Decimal = Decimal.Parse(width)
        If widtha < 0 Then
            MsgBox("Width can not be negative.")
            Return
        End If
        Dim calculations1 As Decimal = lengtha * widtha
        AnswerLabel.Content = "Area: " + calculations1.ToString
        Dim calculations2 As Decimal = lengtha * 2 + widtha * 2
        answerLabel2.Content = "Perimeter: " + calculations2.ToString
    Catch ex As Exception

    End Try
End Sub

```

End Class