Member Avatar for shubhamshah

Hey Guys,
Im not so good at VB.NET , and ive been learning for about 3 months. I would really appreciate it if you guys would help me tackle this problem down.

Well , im helping a school run a Spelling Bee aimed at children in year 7. And to make it fair and unbiased i need an application that can choose randomise a word from the list box then transfer the string to the text box.

So basically something that can pick a random string from the listbox and show it in the textbox1.text property.

Once again , Thanks in advance. I would love it if you guys could help me with this problem. I cant seem to do it with the skills i currently have.

Bye

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  • Latest Post Latest Post by kvprajapati

Dani AI

Generated

Good progress — and nice teamwork: pointed you toward using a random-number generator and suggested removing the picked item. A couple of small but important improvements will make the routine robust and fair for a school Spelling Bee:

  • Never call the Random constructor each click (it can re-seed to the same value when clicks are close together). Keep one Random for the form.
  • Guard against an empty list before calling Next.
  • Use the correct Next upper bound (pass Count, not Count - 1).
  • Store the chosen index/value in a variable before removing it.

Example: put a single Random instance on the form and pick/remove safely.

' form-level
Private Shared rnd As New Random()

' click handler
Private Sub btnPick_Click(sender As Object, e As EventArgs) Handles btnPick.Click
    If ListBox1.Items.Count = 0 Then
        TextBox1.Clear()
        btnPick.Enabled = False
        Return
    End If

    Dim idx As Integer = rnd.Next(ListBox1.Items.Count)       ' 0 .. Count-1
    Dim word As String = Convert.ToString(ListBox1.Items(idx))
    TextBox1.Text = word
    ListBox1.Items.RemoveAt(idx)
    lblRemaining.Text = "Remaining: " & ListBox1.Items.Count.ToString()
End Sub

If you want to avoid doing a random pick each time, shuffle the pool once (Fisher-Yates) and then take items in order — this is simple, unbiased, and reproducible:

Private Sub Shuffle(Of T)(items As List(Of T))
    For i As Integer = items.Count - 1 To 1 Step -1
        Dim j As Integer = rnd.Next(i + 1)
        Dim tmp As T = items(i)
        items(i) = items(j)
        items(j) = tmp
    Next
End Sub

Extra tips: keep a separate copy of the original word list if you need to reset rounds, trim/validate each word (typos like "Astronaughts" are easy to miss), and disable the pick button when the pool is empty. These small checks will prevent exceptions and make the Spelling Bee run smoothly.

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Member Avatar for apegram

Have you tried using a Random object?

Perhaps consider generating a random number between 0 and the number of items in the ListBox control. With that number, you can select an item and use that to populate the TextBox.

Edited by apegram because: n/a
Member Avatar for shubhamshah

How can i do that in code. Im not so sure . Sorry buddy. =( Thanks alot though

In the listbox i have the words -
Dinosaur
Space
Astronaughts
Earth
Resolution
Etc

Then i have a label -
Empty

And a button -
Which should include the code of the randomization

Edited by shubhamshah because: n/a
Member Avatar for shubhamshah

Hey , Good News . I was trying to code it. and ive gotten this far.

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim r As New Random
        ListBox1.SelectedIndex = r.Next(0, ListBox1.Items.Count - 1)
        TextBox1.Text = ListBox1.Text
    End Sub

Now how can i delete the item i just transfered from the listbox

Edited by shubhamshah because: n/a
Member Avatar for kvprajapati

>how can i delete the item i just transfered from the listbox?

ListBox1.Items.RemoveAt method.

Member Avatar for shubhamshah

Thanks alot guys - This is my final code

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim r As New Random

        ListBox1.SelectedIndex = r.Next(0, ListBox1.Items.Count - 1)
        TextBox1.Text = ListBox1.Text
        ListBox1.Items.RemoveAt(ListBox1.SelectedIndex)
    End Sub
Member Avatar for kvprajapati

Thanks. Please mark this thread as solved.

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