private void LoadExpiredItems() { Item item = new Item(); if(glkActivity.EditValue != null) { int activityId = (int)glkActivity.EditValue; var dt = item.GetExpiredItemsByActivity(activityId); dt.Columns.Add( new DataColumn() { ColumnName = "IsSelected", DataType = typeof(bool), DefaultValue = false, AllowDBNull = true, } ); grdExpiredItems.DataSource = dt; } }