在WinForms .Net 3.5中的CheckedListBox中没有DisplayMember

public class CustomCheckedListBox : CheckedListBox
{
    public CustomCheckedListBox()
    {
        this.ItemCheck += CustomCheckedListBox_ItemCheck;
    }

    private void CustomCheckedListBox_ItemCheck(object sender, ItemCheckEventArgs e)
    {
        e.NewValue = e.CurrentValue;
    }

    protected override void OnDrawItem(DrawItemEventArgs e)
    {
        if (e.Index >= 0 && e.Index< Items.Count)
        {
            object item = Items[e.Index];
            string itemText = GetItemText(item);

            e.DrawBackground();
            using (SolidBrush brush = new SolidBrush(e.ForeColor))
            {
                e.Graphics.DrawString(itemText, e.Font, brush, e.Bounds);
            }

            if ((e.State & DrawItemState.Focus) == DrawItemState.Focus)
            {
                e.DrawFocusRectangle();
            }
        }
        else
        {
            base.OnDrawItem(e);
        }
    }
}

public class CustomCheckedListBox : CheckedListBox
{
    public CustomCheckedListBox()
    {
        this.ItemCheck += CustomCheckedListBox_ItemCheck;
        this.Format += CustomCheckedListBox_Format;
    }

    private void CustomCheckedListBox_ItemCheck(object sender, ItemCheckEventArgs e)
    {
        e.NewValue = e.CurrentValue;
    }

    private void CustomCheckedListBox_Format(object sender, ListControlConvertEventArgs e)
    {
        e.Value = GetItemText(e.ListItem);
    }

    protected override void OnDrawItem(DrawItemEventArgs e)
    {
        if (e.Index >= 0 && e.Index< Items.Count)
        {
            object item = Items[e.Index];
            string itemText = GetItemText(item);

            e.DrawBackground();
            using (SolidBrush brush = new SolidBrush(e.ForeColor))
            {
                e.Graphics.DrawString(itemText, e.Font, brush, e.Bounds);
            }

            if ((e.State & DrawItemState.Focus) == DrawItemState.Focus)
            {
                e.DrawFocusRectangle();
            }
        }
        else
        {
            base.OnDrawItem(e);
        }
    }
}