protected override System.Web.UI.Control AddEditor(System.Web.UI.Control container)
        {
            var multiSelect = new MultiSelect { ID = Name };

            multiSelect.Items.AddRange(GetListItems());
            Configure(multiSelect);
            container.Controls.Add(multiSelect);
            return multiSelect;
        }
 protected virtual void Configure(MultiSelect ddl)
 {
     ddl.SearchTreshold = SearchTreshold;
 }
		protected virtual void Configure(MultiSelect ddl)
		{
			ddl.EnableFilter = SearchTreshold >= 0 && ddl.Items.Count >= SearchTreshold;
			ddl.SelectedList = byte.MaxValue;
		}