Try-Catch problems

[darkhunterd]

Hello, i'm kinda a newbie in a lot of things related to vb. I can't seem to find the error regarding one function that i made that uses a try-catch code but it really doesn't do anything.

read in the book so this is the last modification
http://www.nomorepasting.com/getpaste.php?pasteid=12033

my first one was like this
http://www.nomorepasting.com/getpaste.php?pasteid=12034

neither perform try-catch as supposed.

Please help i really want to know what i'm doing wrong .

thanks for your help

P.S. sorry if i posted on the wrong section

 

[Fremus]

hi

i i understood your problem well - you need to trap the division by zero?

I teted out as follows and it worked:

    Private Function decimalsum(ByVal den1 As Decimal, ByVal den2 As Decimal, ByVal num1 As Decimal, ByVal num2 As Decimal) As Double
        Dim partialResult1, partialResult2, decimalresult As Double

        Try
            partialResult1 = num1 / den1
        Catch Exception As DivideByZeroException
            MessageBox.Show("Trato de dividir por cero")
        End Try

        Try
            partialResult2 = num2 / den2
        Catch Exception As DivideByZeroException
            MessageBox.Show("Trato de dividir por cero")
        End Try

        decimalresult = partialResult1 + partialResult2

        Return decimalresult
    End Function

and to test the code:

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim result = decimalsum(0, 0, 1, 1)
    End Sub

The message box was shown

HTH

 

[darkhunterd]

oh good, thanks

but exactly what did i have wrong? or what did i have right? i really want to learn

 

[Fremus]

hmmm

well i just included "ByVal den1 As Decimal," - the As Decimal...

you can always create another catch statement that will handle ALL errors

example:

        Try
            partialResult1 = num1 / den1
        Catch Exception As DivideByZeroException
            MessageBox.Show("Trato de dividir por cero")
        Catch ex As Exception
            MessageBox.Show(ex.Message)
        End Try

        Try
            partialResult2 = num2 / den2
        Catch Exception As DivideByZeroException
            MessageBox.Show("Trato de dividir por cero")
        Catch ex As Exception
            MessageBox.Show(ex.Message)
        End Try

 

[JohnH]

Your function doesn't return a correct result if den1/den2 is 0, so you should throw ArgumentException if this is the case.

Private Function decimalsum(ByVal den1 As Double, ByVal den2 As Double, ByVal num1 As Double, ByVal num2 As Double) As Double
    If den1 = 0 OrElse den2 = 0 Then
        Throw New ArgumentException("den1/den2 parameters values cannot be 0.")
    End If
    Return (num1 / den1) + (num2 / den2)
End Function

Try
    Dim d As Double = decimalsum(0, 1, 1, 1)
Catch ex As Exception
    MsgBox(ex.Message)
End Try