Question

I have Class Supplier with 2 data member are SupID and SupplierName and 1 Constructor then I add this objects into List of Supplier when Form1 load().

    Dim lst As New List(Of Supplier)

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
       AddList()
    End Sub

    Public Sub AddList()
       lst.Add(New Supplier("Sup1", "Supplier1"))
       lst.Add(New Supplier("Sup2", "Supplier2"))
       lst.Add(New Supplier("Sup3", "Supplier3"))
       lst.Add(New Supplier("Sup4", "Supplier4"))
       lst.Add(New Supplier("Sup5", "Supplier5"))
    End Sub

And then I want to send lst to Form2 by its new instant constructor when I click Send Button:

    Private Sub cmdSend_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdSend.Click
       Dim frm As New Form2(lst)
       frm.Show(Me)
    End Sub

Next In form2, code like this:

    Dim lst As New List(Of Supplier)
    Dim bs As BindingSource

    Public Sub New(ByVal lst As New List(Of Supplier)
       Me.InitializeComponent()
       Me.lst = lst
       bs = new BindingSource(lst,nothing)
    End Sub

And then I want to remove the object from bs:

    Public Sub cmdRemove_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdRemove.Click
       bs.RemoveCurrent()
    End Sub

The problem is that, when i remove the object from bs in Form2, the object in lst in Form1 is affected too. So how can I do if I don’t want the list in Form1 affect?

Thank you in advance….

Answer 1

Try changing the code in Form2 to this:

Dim lst As List(Of Supplier)
Dim bs As BindingSource

Public Sub New(ByVal lst As List(Of Supplier))
   Me.InitializeComponent()
   Me.lst = New List(Of Supplier)(lst)
   bs = new BindingSource(Me.lst, Nothing)
End Sub