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كود :
#Region " Swap ListBox Items by DragDrop "

    Private Sub List_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles ListBox2.MouseDown, ListBox1.MouseDown

        If Windows.Forms.MouseButtons.Right Then

            sender.SelectedIndex = sender.IndexFromPoint(e.X, e.Y)

            If sender.SelectedIndex < 0 Then Exit Sub

            sender.DoDragDrop(sender.SelectedIndex.ToString, DragDropEffects.Move)

        Else

            sender.SelectedIndex = sender.IndexFromPoint(e.X, e.Y)

            If sender.SelectedIndex < 0 Then Exit Sub

            sender.DoDragDrop(sender.SelectedIndex.ToString, DragDropEffects.None)

        End If

    End Sub

    Private Sub List_DragOver(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) Handles ListBox2.DragOver, ListBox1.DragOver

        If Windows.Forms.MouseButtons.Right Then



            e.Effect = DragDropEffects.Move

            Dim pt As Point = sender.PointToClient(New Point(e.X, e.Y))

            Dim drop_index As Integer = sender.IndexFromPoint(pt.X, pt.Y)

            sender.SelectedIndex = drop_index

        End If

    End Sub

    Private Sub List_DragDrop(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) Handles ListBox2.DragDrop, ListBox1.DragDrop

        If sender.SelectedIndex < 0 Then Exit Sub

        Dim SelectedIndex As Integer = sender.SelectedIndex

        Dim i1 As Integer = Int(e.Data.GetData(DataFormats.Text).ToString), i2 As Integer = sender.SelectedIndex

        If i1 > i2 Then

            Dim a As Integer = i1

            i1 = i2 : i2 = a

        End If

        SwapItems(ListBox2, i1, i2)

        SwapItems(ListBox1, i1, i2)

        sender.SelectedIndex = SelectedIndex

    End Sub

    Private Sub SwapItems(ByVal ListBox As ListBox, ByVal SelectedIndex1 As Integer, ByVal SelectedIndex2 As Integer)

        Dim itm1 As Object = ListBox.Items(SelectedIndex1)

        Dim itm2 As Object = ListBox.Items(SelectedIndex2)

        ListBox.Items.RemoveAt(SelectedIndex1)

        ListBox.Items.Insert(SelectedIndex1, itm2)

        ListBox.Items.RemoveAt(SelectedIndex2)

        ListBox.Items.Insert(SelectedIndex2, itm1)

    End Sub

#End Region