Question

Check out the simple code below :

Public Class Form1
    Private _items As List(Of String) = New List(Of String)
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        _items.Add("Item1")
        _items.Add("Item2")
        _items.Add("Item3")

        ListBox1.DataSource = _items
        ListBox2.DataSource = _items
    End Sub
End Class

What happens is that when the Item2 is selected in the first listbox, the second listbox automatically changes its selected item to the Item2. This happens just the same with the other listbox.

Any idea why this is happening?

Answer 1

That’s because your two ListBoxes are sharing the form’s default BindingContext object. To change this, explicitly create a BindingContext for each ListBox.