从bindinglist获取已删除项目的索引

Question

我能够获得添加到BindingList的项目索引.当我尝试获取索引时,如果删除的项目我得到错误

Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index

这是我的代码

Private Sub cmdRemove_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdRemove.Click

    For i As Integer = 0 To _assignedSelection.SelectedCount - 1
        Dim item As Jurisdiction = CType(_assignedSelection.GetSelectedRow(i), Jurisdiction)
        _list.Remove(item)
    Next

End Sub


Private Sub list_Change(ByVal sender As Object, ByVal e As ListChangedEventArgs) Handles _list.ListChanged

    If (_list.Count > 0) Then


        Select Case e.ListChangedType
            Case ListChangedType.ItemAdded
                _dal.InsertJurisdiction(_list.Item(e.NewIndex))
            Case ListChangedType.ItemDeleted
                'MsgBox(e.NewIndex.ToString)
                _dal.DeleteJurisdiction(_list.Item(e.NewIndex)) <--------HERE
        End Select

    End If

End Sub

编辑:C#中的答案也欢迎....任何人？

Answer 1

事件触发前,该项目将被删除.这意味着(没有附加代码)您无法访问要删除的项目.

但是,您可以从BindingList继承,并覆盖RemoveItem:

public class BindingListWithRemoving<T> : BindingList<T>
{
    protected override void RemoveItem(int index)
    {
        if (BeforeRemove != null)
            BeforeRemove(this, 
                  new ListChangedEventArgs(ListChangedType.ItemDeleted, index));

        base.RemoveItem(index);
    }

    public event EventHandler<ListChangedEventArgs> BeforeRemove;
}

您还应该复制BindingList构造函数.此外,不要试图使其可取消,因为呼叫者可能会认为呼叫Remove确实删除了该项目.