I had to take a VB.NET test today

[VBGuy]

I had to take a VB.NET test today for an employer. This question was included.

If you run the code below what will the value of label1.Text

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim i As Double
        Dim s As String
        Try
            s = "i = "
            i = 1 / 0
            s = s & "infinity"
        Catch
            s = s & "undefined"
        Finally
            label1.Text = s
        End Try
End Sub

My answer was "i = infinity" but was told I was wrong. Can someone explain how I am wrong? They told me the correct answer is "i = undefined". I think they caught themselves in their own trick question.

[SimonVega]

Because when you try to divide 1 by 0, an exception is thrown. In your catch block, you append on 'undefined' to the string. Then, when the finally block executes, the label's caption is updated. Hey, I'm from cincinnati also.

[Pirate]

Originally posted by SimonVega
Because when you try to divide 1 by 0, an exception is thrown. In your catch block, you append on 'undefined' to the string. Then, when the finally block executes, the label's caption is updated. Hey, I'm from cincinnati also.

No acception is thrown at all ! I tried this code

Dim i As Double
Dim s As String
 
s = "i = "
 i = 1 / 0
s = s & "infinity"
Label1.Text = s

So you fooled by Catch structure .

[Pirate]

exception not acception

[SimonVega]

Hmm....I didn't try the code, im not at my dev machine, just eye ballin' it, it seems that would be the cause....Oh well, can't always be right!

[VBGuy]

I think the person that wrote the code expected the 1/0 to throw an error but it doesn't. .NET defines a divide by zero as infinity.

Try this code

label1.Text = 1 / 0

[Edneeis]

You should get a divid by zero error.

That is wierd though, because you don't. Hmmm.

Ahh its because they have or the post has the division slash backwards. So it means something else and not division and thus no error.

You should black their eye for marking you off.

I think they meant this:

Dim i As Integer = 1
        Dim s As String
        Try
            s = "i = "
            i = i \ 0
            s = s & "infinity"
        Catch
            s = s & "undefined"
        Finally
            Me.Text = s
        End Try

[VBGuy]

It will give you a compile error if you do integer division 1\0 but will evaluate 1/0 as infinity.

[SimonVega]

When I try the same example in C#, the compiler will not even let you run the application.

[Edneeis]

I guess in VB the / returns a floating point and thus the #INF but the \ returns an integer and gives the error.

[VBGuy]

Well, a compile error was not an option so they expected it to throw an error.

Based on this (and several other issues), I told them I was no longer interested in the posistion.

[SimonVega]

What was the name of the company? What part of cincinnati you from?

[MrPolite]

this might be helpful
when you divide by zero .NET wont throw an exception error. I think it's only like this for Double. There is Double.isNaN and Double.IsInfinity
Nan is Not A Number, I dont remember when that happens.
Now if you try this with that code it will return true : Double.IsInfinity(i)

I think they made it like this so that your program wouldnt return an exception for these values. Makes more sense..... there was an explanation of it in my book...


edit: and the reason that it doesnt work with "\" is that "\" converts the value to INTEGER. But the Integer data type doesnt accept the values of Infinity or Nan

[VBGuy]

SimonVega, check your prvate messages

[DevGrp]

This is a long shot, but it may throw an exception if option explicit or option strict is on.

[VBGuy]

DevGrp, turning option strict only makes you have to convert the infinity to a string


label1.Text = CStr(1 / 0)

[Hu Flung Dung]

Originally posted by VBGuy
I had to take a VB.NET test today for an employer. This question was included.

If you run the code below what will the value of label1.Text

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim i As Double
        Dim s As String
        Try
            s = "i = "
            i = 1 / 0
            s = s & "infinity"
        Catch
            s = s & "undefined"
        Finally
            label1.Text = s
        End Try
End Sub

My answer was "i = infinity" but was told I was wrong. Can someone explain how I am wrong? They told me the correct answer is "i = undefined". I think they caught themselves in their own trick question.

I just ran your code, and I get "i = infinity". Their completely wrong!!!!

The double data type allows for NaN's and infinities.

[MrPolite]

Originally posted by Hu Flung Dung
I just ran your code, and I get "i = infinity". Their completely wrong!!!!

The double data type allows for NaN's and infinities.

that's what I said

[vbpahuja]

You were perfectly correct!!

Go back & tell them that they are not good enough for you to work for them!!