Visual Basic

' Create a ListBox
Dim testBox As ListBox = New ListBox()
testBox.Parent = Me
testBox.Dock = DockStyle.Fill
testBox.SelectionMode = SelectionMode.MultiSimple
Me.Controls.Add(testBox)

' Add some testitems
Dim i As Integer
For i = 0 to 10
   testBox.Items.Add ("test " & i)
Next i

' Select items 2 & 7
testBox.SelectedItems.Clear()
testBox.SelectedItems.Add(testBox.Items(2))
testBox.SelectedItems.Add(testBox.Items(7))

' Iterate all items, verifying if they're selected
For Each someItem in testBox.Items
	If (testBox.SelectedItems.Contains(someItem)) Then
		Debug.WriteLine(someItem & " was selected")
	End If
Next someItem

' Or, iterate the selected ones only;
For Each selectedItem In testBox.SelectedItems
	Debug.WriteLine(selectedItem & " was selected")
Next

I are Troll

For Each someItem in testBox.Items
	If testBox.SelectedItems.Contains(someItem) Then
		MessageBox.Show(someItem & " is selected")
	else
		MessageBox.Show(someItem & " is not selected")
	End If
Next someItem

Dim SelectedItemsList As New List(Of String)
        For Each SelectedItem As String In ListBox1.SelectedItems
            SelectedItemsList.Add(TextBox1.Text)
        Next

If SelectedItemList = ListBox.Items Then
'Selected
Else
'Not selected
End If

For Each item As String In ListBox1.Items
    If ListBox1.SelectedItems.Contains(item) Then
        ' do something with the selected item (it should not change the ListBox)
    Else
        ' do something with the unselected item (it should not change the ListBox)
    Endif
Next

For Each item As String In ListBox1.Items
    If ListBox1.SelectedItems.Contains(item) Then
        MessageBox.Show(item & "|" & True)
    Else
        MessageBox.Show(item & "|" & False)
    End If
Next

Private Sub ListBox1_SelectedValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListBox1.SelectedValueChanged
    Dim s As String = ""
    For i As Integer = 0 To ListBox1.Items.Count - 1
        Dim item As String = ListBox1.Items(i)
        If ListBox1.SelectedItems.Contains(item) Then
            s = s & " +" & item
        Else
            s = s & " -" & item
        End If
    Next
    Label1.Text = s
End Sub

Andraw Tang wrote:

Can you give me some suggenstion how to organize the form for this case? I don't want to show all data at the same time, then if user select type 1, enable type 1 data set and disable other two sets.

I are Troll

Andraw Tang wrote:

If I use panels to hold data, I should overlap these panels and make one of them visible according to user selection, right?

Andraw Tang wrote:

What did you mean to move it to UserControl?

Public Class MyPanel
    Inherits System.Windows.Forms.UserControl
		
    Public Name As String
		
End Class

I are Troll

soulrebelpd wrote:

I learned what I know about Ms Access from "reverse engineering" an application(as well as reading books of course).

soulrebelpd wrote:

I just purchased a book Murach's ado.net vb2008, it has a good amount of sample applications so hopefully it will help.