Visual Basic: Comparing ListBoxes

[Daniel Martos]

I have 2 ListBoxes.  ListBox1 is populated with 5 selected numbers from a CheckedListBox(LotteryBox) and ListBox2 is populated with random numbers 1-99.  I want to find a way to verify if the numbers in the two ListBoxes match.  For Example, if they matched one number.  It'll say "You've matched one number".  and so on.  I think I'm on the right path with:

   Dim Matched As Integer = 0
        If ListBox2.Contains((LotteryBox.SelectedItem)) Then Matched += 1
        If ListBox2.Contains((LotteryBox.SelectedItem)) Then Matched += 1
        If ListBox2.Contains((LotteryBox.SelectedItem)) Then Matched += 1
        If ListBox2.Contains((LotteryBox.SelectedItem)) Then Matched += 1
        If ListBox2.Contains((LotteryBox.SelectedItem)) Then Matched += 1

But how do I differentiate between the five numbers selected in the LotteryBox?

[Campbell Ritchie]

Can you make the selected items in each of the boxes into a collection and do anything like this on it? That will avoid your having to iterate the box 5×.

Duplicating discussion in our VB forum.

[Daniel Martos]

Campbell Ritchie wrote:Can you make the selected items in each of the boxes into a collection and do anything like this on it? That will avoid your having to iterate the box 5×.

Duplicating discussion in our VB forum.

I'm not real sure how to to that.  Here's the entire code:

   Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        'list to store numbers
        Dim numbers As New List(Of Integer)

        'add desired numbers to list
        For count As Integer = 1 To 99
            numbers.Add(count)
        Next


        Dim Rnd As New Random
        Dim SB As New System.Text.StringBuilder
        Dim Temp As Integer

        'select a random number from the list, add to listbox and remove it so it can't be selected again
        For count As Integer = 1 To 5
            Temp = Rnd.Next(0, numbers.Count)
            SB.Append(numbers(Temp) & "  ")
            ListBox2.Items.Add(numbers(Temp))
            numbers.RemoveAt(Temp)
        Next
        Dim numIndex As Integer
        For numIndex = 0 To LotteryBox.Items.Count - 1
            If LotteryBox.GetItemChecked(numIndex) = True Then ListBox1.Items.Add(LotteryBox.Items(numIndex))
        Next
    End Sub
End Class

[Daniel Martos]

I tried to create a collection, as suggested.  I received an error stating that Unable to cast object of type 'System.Int32' to type 'System.Windows.Forms.Control'

 Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        'list to store numbers
        Dim numbers As New List(Of Integer)
        [color=yellow]Dim lotteryPicks As New Collection[/color]
        'add desired numbers to list
        For count As Integer = 1 To 99
            numbers.Add(count)
        Next


        Dim Rnd As New Random
        Dim SB As New System.Text.StringBuilder
        Dim Temp As Integer

        'select a random number from the list, add to listbox and remove it so it can't be selected again
        For count As Integer = 1 To 5
            Temp = Rnd.Next(0, numbers.Count)
            SB.Append(numbers(Temp) & "  ")
            ListBox2.Items.Add(numbers(Temp))
            [color=yellow]lotteryPicks.Add(numbers(Temp))[/color]
            numbers.RemoveAt(Temp)
        Next
        Dim numIndex As Integer
        For numIndex = 0 To LotteryBox.Items.Count - 1
            If LotteryBox.GetItemChecked(numIndex) = True Then ListBox1.Items.Add(LotteryBox.Items(numIndex))
        Next
        [color=yellow]Dim Matched As Integer = 0
        If ListBox1.Contains(lotteryPicks.Item(1)) Then Matched += 1
        If ListBox1.Contains(lotteryPicks.Item(2)) Then Matched += 1
        If ListBox1.Contains(lotteryPicks.Item(3)) Then Matched += 1
        If ListBox1.Contains(lotteryPicks.Item(4)) Then Matched += 1
        If ListBox1.Contains(lotteryPicks.Item(5)) Then Matched += 1

        LabelOutput.Text = "You've matched " & Matched & " Numbers"[/color]
    End Sub
End Class