Visual Basic 2010 Express - Need Help Passing Data from CheckedListBox to TextBox

[crisstoph]

I am very new to programming, so please bare with me. I am using VB 2010 express and am trying to make a program for a project that generates lottery numbers in a specific way. What I have is two forms. Form one has two text boxes and a button. Form two has a checkedlistbox that is pre-populated with numbers from 1-56. What I am trying to do is have the program open to form1, the user presses button1 ("Select Numbers") which opens form2. From there they will select numbers they want to pick from (narrowing their pool of lotto picks to only numbers they want to use). Then when they hit select, I want the numbers they have checked to return back to the textbox1 on form1. HOWEVER, I also only want 5 numbers, randomly selected, from the pool of checked numbers the user selected on form2 to return to the textbox1 on form1..... I may be in wayyy over my head, but I have all of the forms designed and I have been close to getting the forms to at least communicate, but still far from doing what I have described I am trying to do. Any and all help would be greatly appreciated at this point!!!

[crisstoph]

Code I have been trying:

Form1:
Public Class Form1
Inherits System.Windows.Forms.Form
Dim NumberSelect As Form2
Private Property CheckedListBox1 As Form2
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
Using dialogue As New Form2
dialogue.ShowDialog()
Me.TextBox1.Text = dialogue.checkedlistbox
End Using
End Sub

Form2:
Public Class Form2

Public Property checkedlistbox As String
Get
Return Me.CheckedListBox1.Text
End Get
Set(value As String)
Me.CheckedListBox1.Text = value
End Set
End Property

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
If CheckedListBox1.CheckedItems.Count > 0 Then
Form1.Show()
Form1.TextBox1.Text = checkedlistbox
Else
MessageBox.Show("select numbers")
End If
End Sub

------
This code will return the last item checked in the checkedlistbox to the textbox in form1. It will not return all checked items. I was trying to at least get that far before I even attempted to figure out how to take the list of checked items, randomize them, and only display five of those randomized numbers in the textbox on form1.

[dglienna]

Look up the RANDOM() command. You can pick from a start index to the end index. Keep another list of YES or NO answers for each entry. See the steps?

[crisstoph]

I now have the code working to send all of the checked items in checkbox1 on form2 to textbox1 on form1. Which I wanted to get working before I moved on to try to learn how to now just get 5 of the numbers randomly from those selected on the checkedlistbox (i.e. If the user selects 20 numbers on the checkedlistbox on form2 and hits submit, the program will take 5 of those 20 selected randomly and return them to the textbox on form1). Here is how I have done that:

Public Class Form1

Inherits System.Windows.Forms.Form

Dim NumberSelect As Form2

Private Property CheckedListBox1 As Form2
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
Using dialogue As New Form2
dialogue.ShowDialog()
Me.TextBox1.Text = dialogue.TextBoxText
End Using
End Sub
End Class

Public Class Form2
Public Property TextBoxText() As String
Get
Return Me.TextBox3.Text
End Get
Set(value As String)
Me.TextBox3.Text = value
End Set
End Property

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Randomize()
Dim i As Integer = 0
' Loop through all the selected items of the listbox and append them to the textbox text property
For i = 0 To CheckedListBox1.CheckedItems.Count - 1
TextBox3.Text &= CheckedListBox1.CheckedItems.Item(i).ToString() & " "
Next
End Sub
End Class

----------------
I have a little more knowledge of the Random() command, but still am lost in how to incorporate it to do what I am trying to do.

[dglienna]

i is the key. compute a random between 0 and max-1

TextBox3.Text &= CheckedListBox1.CheckedItems.Item(i)

[crisstoph]

I'm not sure if I have made this as simple as you are suggesting, but you have at least sent me in the right direction. Now I have a code that is working to return 5 random numbers from the numbers that are checked back to the textbox1 on form1, but it always gives me one duplicate number (i.e "2, 53, 2, 42, 52"). What is the simplest way to prevent this code from choosing the same number from the pool twice, and why is it happening every time? Here is the new code:

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

Form1.TextBox1.Clear()

Dim randomNumber As Integer

Dim i As Integer = 0


If Integer.TryParse(5, i) AndAlso i <= Me.CheckedListBox1.CheckedItems.Count Then
Do While i <> 0
randomNumber = Rnd.Next(0, Me.CheckedListBox1.CheckedItems.Count - 1)
TextBox3.Text &= (Me.CheckedListBox1.CheckedItems(randomNumber)).ToString() & " "
i -= 1 'not sure what this line does...
Loop

End If

End Sub

[crisstoph]

Update: I thought I had found my issue with the repeating numbers. I thought I needed to define "randomnumber" as "New Integer", not just "Integer" AND add "If randomnumber = 0...." But that didn't work either, I am still getting duplicate numbers.
I would also like to determine if there is a way to do something else, and please let me know if I need to start a new thread for it, but what I would like to do to complete this project is to find a way to have form2 not clear the checked boxes from the previous time it was used when it is opened again AND a way to be able to save the checked boxes so a user can recall their selections when they open the program... Thanks for all your help so far!

The most recent code I am using to get the 5 random selections from the checked items is as follows:

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

Form1.TextBox1.Clear()

Dim randomNumber As New Integer
Dim i As Integer = 0
If randomNumber = 0 AndAlso Integer.TryParse(5, i) AndAlso i <= Me.CheckedListBox1.CheckedItems.Count Then
Do While i <> 0
randomNumber = rnd.Next(0, Me.CheckedListBox1.CheckedItems.Count - 1)
TextBox3.Text &= (Me.CheckedListBox1.CheckedItems(randomNumber)).ToString() & " "
i -= 1
Loop
End If

End Sub

[dglienna]

Set up another field (of whatever TYPE you want. String would work)

If they correspond to the choices, you set them all to 0 to start. Then, as you pick one, you check to make sure that it's 0 in the PICKED() field. If so, change to 1, and you have a unique pick.

I use that method to pick cards...