visual basic quiz

[marioman681]

hi all, im new here and joined today as im stuck programming a visual basic quiz.

I cannot get my questions to appear on the buttons on visual basic 2008 and do not not why not.

thanks

Function randomquestion()
        Dim randomvalue As Integer
        randomvalue = 30
        randomvalue = Int(Rnd() * 20) + 1

        Select Case randomvalue
            Case 1
                quebox.Text = "what is 100+29?"
                Button1.Text = "129"
                Button2.Text = "10029"
                Button3.Text = "130"
                Button4.Text = "1029"
            Case 2
                quebox.Text = "what is 89+12?"
                Button1.Text = "101"
                Button2.Text = "100"
                Button3.Text = "110"
                Button4.Text = "102"
            Case 3
                quebox.Text = "what is 10X6?"
                Button1.Text = "60"
                Button2.Text = "106"
                Button3.Text = "600"
                Button4.Text = "16"
            Case 4
                quebox.Text = "what is 2X4?"
                Button1.Text = "8"
                Button2.Text = "24"
                Button3.Text = "12"
                Button4.Text = "4"
            Case 5
                quebox.Text = "what is 100-40?"
                Button1.Text = "60"
                Button2.Text = "50"
                Button3.Text = "70"
                Button4.Text = "80"
            Case 6
                quebox.Text = "what is 99+11?"
                Button1.Text = "109"
                Button2.Text = "110"
                Button3.Text = "111"
                Button4.Text = "120"
            Case 7
                quebox.Text = "what is 44+44?"
                Button1.Text = "80"
                Button2.Text = "88"
                Button3.Text = "84"
                Button4.Text = "4444"
            Case 8
                quebox.Text = "what is 50-30?"
                Button1.Text = "10"
                Button2.Text = "20"
                Button3.Text = "30"
                Button4.Text = "40"
            Case 9
                quebox.Text = "what is 55+36?"
                Button1.Text = "90"
                Button2.Text = "91"
                Button3.Text = "81"
                Button4.Text = "101"
            Case 10
                quebox.Text = "what is 109+12?"
                Button1.Text = "120"
                Button2.Text = "121"
                Button3.Text = "116"
                Button4.Text = "112"
            Case 11
                quebox.Text = "what is 10X3?"
                Button1.Text = "103"
                Button2.Text = "13"
                Button3.Text = "30"
                Button4.Text = "40"
            Case 12
                quebox.Text = "what is 50+40?"
                Button1.Text = "80"
                Button2.Text = "100"
                Button3.Text = "90"
                Button4.Text = "70"
            Case 13
                quebox.Text = "what is 70+25?"
                Button1.Text = "85"
                Button2.Text = "115"
                Button3.Text = "105"
                Button4.Text = "106"
            Case 14
                quebox.Text = "what is 80+25?"
                Button1.Text = "85"
                Button2.Text = "115"
                Button3.Text = "105"
                Button4.Text = "106"
            Case 15
                quebox.Text = "what is 10X9?"
                Button1.Text = "109"
                Button2.Text = "19"
                Button3.Text = "90"
                Button4.Text = "100"
            Case 16
                quebox.Text = "what is 100X2?"
                Button1.Text = "1002"
                Button2.Text = "102"
                Button3.Text = "100"
                Button4.Text = "200"
            Case 17
                quebox.Text = "what is 100-55?"
                Button1.Text = "55"
                Button2.Text = "65"
                Button3.Text = "35"
                Button4.Text = "45"
            Case 18
                quebox.Text = "what is 45+40?"
                Button1.Text = "95"
                Button2.Text = "75"
                Button3.Text = "80"
                Button4.Text = "85"
            Case 19
                quebox.Text = "what is 60+34?"
                Button1.Text = "84"
                Button2.Text = "104"
                Button3.Text = "90"
                Button4.Text = "94"
            Case 20
                questionlabel.Text = "what is 100+19?"
                Button1.Text = "120"
                Button2.Text = "109"
                Button3.Text = "1019"
                Button4.Text = "119"
            Case Else
                MsgBox("cannot produce a question at this time")
        End Select
    End Function

[Shaggy Hiker]

Welcome to the forums, then.

So, what is not showing up? Just the button text? There doesn't appear to be anything wrong with that part (the bit about using the archaic Rnd method is another story). It would be really weird if something is showing up in the quebox, yet not on the buttons.

Basically, I would guess that it is doing the right thing, but that something else is undoing it later on. The thing to do is to put a breakpoint in the first line of the method, then step through the code seeing what happens. If it does, indeed, assign some text to the buttons, step on out of the function (using F11, not F10) and see what happens. Perhaps you are triggering an event that immediately erases what you just wrote.

[marioman681]

Hi again, nothing appears in the question box either. I think it could be to do with an error I get at the end of the function which says a value can't e returned on all paths, but I don't know how to stop this error

Cheers again

[Shaggy Hiker]

Nope, it has nothing to do with that error. The error comes from the fact that a Function has to return a value. You aren't returning anything, nor does it look like you need to be, in which case you should be using a Sub rather than a Function.

If you are getting nothing in any of those controls, and you aren't getting the messagebox at the end, then the code isn't being called at all, which almost certainly means that the whole function isn't being called at all. You can test this quickly and easily by putting a breakpoint on the first executable line in the method, such as the one that creates the random number (that isn't first, but it is good enough). If the execution hits the breakpoint, then you know the function is being called, if it doesn't, then the problem is somewhere else other than in the code you showed.

[marioman681]

when I use the breakpoints it says the breakpoints cannot be hit as no executable code is associated with the lines. as you can tell im new to VB as well and dont know how to solve this problem which is probably relatively simple

thanks again

[Omgitsme]

Did you try using a list, then a function that returns then random number, when the button is pressed quebox = functioname

Declaring a listbox:

Dim GenerateNumber As New Random
    Dim MyNumberList As New List(Of Integer)

Then you would make a function such as this:

Function PrintRandomNumber(ByVal ListOfNumbers As List(Of Integer)) As String
        Dim ChosenNumber As Integer = ListOfNumbers(GenerateNumber.Next(ListOfNumbers.Count))
        ListOfNumbers.Remove(ChosenNumber)
        Return ChosenNumber.ToString
    End Function

Then add a For statement in the button press to add the number of questions you have:

For AddToNumberList As Integer = 1 To 19
            MyNumberList.Add(AddToNumberList)
        Next

Under that for statement you would make the quebox = that number:

quebox.Text = PrintRandomNumber(MyNumberList)

Then add IF and ElseIF statments under that:

If quebox.Text = 1 then
quebox.text = "your question"
button1.text = "answer"
End If

And so on.

[marioman681]

hi, would I have to do that last section 20 times for the questions?

[marioman681]

I think the main issue now is the fact that the breakpoints cannot be hit as no executable code is associated with the lines, if anyone knows how to get the code to run the section I posted in the first post it would be a major help, thanks!

[techgnome]

well, what's the rest of the code look like? how are you calling the sub? Please remember we are not mind readers (as far as I know) and none of us are sitting in your lap (again, as far as I know) so we can't see what you are seeing. We have no concept of what your code looks like ... only what you post. OK, so the code you posted needs to be a Sub rather than a Function ... OK... so what does the rest of the code look like? where is that sub? is it in the form? is it in a class, a module? on a post-it note? on the back of a cocktail napkin?

-tg

[marioman681]

hi again, I had hoped you were mind readers to call it ive got a button that when pressed generate the random question, it has Call questiongen("") as the coding behind the button but it now says argument not specified for parameter 'e'. once again its probably something incredibly simple but im new to vb, thanks again

[techgnome]

post the code.... don't tell us about it.... SHOW us... the error you're giving doesn't jive with anything you've posted so far....

-tg

[marioman681]

hi again, the code is below, Im new to VB remember thank you once again



Public Class matthewtheme
'question counter
Dim questioncounter As Integer
Dim score As Integer
call



Sub questiongen(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load



Dim randomvalue As Integer
randomvalue = 30
randomvalue = Int(Rnd() * 20) + 1

Select Case randomvalue
Case 1
quebox.Text = "what is 100+29?"
Button1.Text = "129"
Button2.Text = "10029"
Button3.Text = "130"
Button4.Text = "1029"
Case 2
quebox.Text = "what is 89+12?"
Button1.Text = "101"
Button2.Text = "100"
Button3.Text = "110"
Button4.Text = "102"
Case 3
quebox.Text = "what is 10X6?"
Button1.Text = "60"
Button2.Text = "106"
Button3.Text = "600"
Button4.Text = "16"
Case 4
quebox.Text = "what is 2X4?"
Button1.Text = "8"
Button2.Text = "24"
Button3.Text = "12"
Button4.Text = "4"
Case 5
quebox.Text = "what is 100-40?"
Button1.Text = "60"
Button2.Text = "50"
Button3.Text = "70"
Button4.Text = "80"
Case 6
quebox.Text = "what is 99+11?"
Button1.Text = "109"
Button2.Text = "110"
Button3.Text = "111"
Button4.Text = "120"
Case 7
quebox.Text = "what is 44+44?"
Button1.Text = "80"
Button2.Text = "88"
Button3.Text = "84"
Button4.Text = "4444"
Case 8
quebox.Text = "what is 50-30?"
Button1.Text = "10"
Button2.Text = "20"
Button3.Text = "30"
Button4.Text = "40"
Case 9
quebox.Text = "what is 55+36?"
Button1.Text = "90"
Button2.Text = "91"
Button3.Text = "81"
Button4.Text = "101"
Case 10
quebox.Text = "what is 109+12?"
Button1.Text = "120"
Button2.Text = "121"
Button3.Text = "116"
Button4.Text = "112"
Case 11
quebox.Text = "what is 10X3?"
Button1.Text = "103"
Button2.Text = "13"
Button3.Text = "30"
Button4.Text = "40"
Case 12
quebox.Text = "what is 50+40?"
Button1.Text = "80"
Button2.Text = "100"
Button3.Text = "90"
Button4.Text = "70"
Case 13
quebox.Text = "what is 70+25?"
Button1.Text = "85"
Button2.Text = "115"
Button3.Text = "105"
Button4.Text = "106"
Case 14
quebox.Text = "what is 80+25?"
Button1.Text = "85"
Button2.Text = "115"
Button3.Text = "105"
Button4.Text = "106"
Case 15
quebox.Text = "what is 10X9?"
Button1.Text = "109"
Button2.Text = "19"
Button3.Text = "90"
Button4.Text = "100"
Case 16
quebox.Text = "what is 100X2?"
Button1.Text = "1002"
Button2.Text = "102"
Button3.Text = "100"
Button4.Text = "200"
Case 17
quebox.Text = "what is 100-55?"
Button1.Text = "55"
Button2.Text = "65"
Button3.Text = "35"
Button4.Text = "45"
Case 18
quebox.Text = "what is 45+40?"
Button1.Text = "95"
Button2.Text = "75"
Button3.Text = "80"
Button4.Text = "85"
Case 19
quebox.Text = "what is 60+34?"
Button1.Text = "84"
Button2.Text = "104"
Button3.Text = "90"
Button4.Text = "94"
Case 20
quebox.Text = "what is 100+19?"
Button1.Text = "120"
Button2.Text = "109"
Button3.Text = "1019"
Button4.Text = "119"
Case Else
MsgBox("cannot produce a question at this time")
End Select
End Sub

[marioman681]

hello again, sorted it out now thanks, the code above works properly.

now though when the question appears its the same one each time, question 15

[Shaggy Hiker]

That is probably due to your use of Rnd. I don't see a call to Randomize anywhere, and without that I have no idea what Rnd will return. You shouldn't be using Rnd anyways, with or without Randomize, because Rnd is legacy. Instead, you should be using the Random object. Create just one instance at form scope, and call the .Next method to get the random number. It's easier than Rnd, anyways.

[marioman681]

hi again, would it be easier to store the questions as I have done above of would it be easier to declare each question and answer eg "dim q1 as string, q1="do you like cheese?"" and then when choosing a random question doing this "Case 1 quebox.Text = q1"?

thanks

[Shaggy Hiker]

I'd store them in a List(of String). After all, if you do it as a bunch of individual variables, you would have to add new variables and new Case statements if you wanted to add a single new question. With a List, you wouldn't need a Case statement, and adding a new item would be as easy as calling List.Add(<your new item here>)