WinForm-SQL查询避免UI卡死

使用委托，呵呵。

Func<List<VM>> act = () =>
            {
                SqlDataReader reader = DBHelper.ExecuteReader(sql);
                List<VM> list = new List<VM>();
                if (reader == null)
                {
                    return null;
                }
                while (reader.Read())
                {
                    VM vm = list.FirstOrDefault(v =>
                        v.sample_lot_no == reader["试批号"].ToString() && v.sample_no == reader["试样号"].ToString());
                    if (vm != null)
                    {
                        vm.test_item_code += "," + ProNameByItem(reader["实验项目"].ToString());
                        continue;
                    }
                    list.Add(new VM()
                    {
                        sample_lot_no = reader["试批号"].ToString(),
                        sample_no = reader["试样号"].ToString(),
                        dateTime = reader["委托时间"].ToString(),
                        test_item_code = ProNameByItem(reader["实验项目"].ToString()),
                        sg_sign = reader["牌号（钢级）"].ToString(),
                        mat_thick = reader["规格"].ToString(),
                        sg_std = reader["标准"].ToString(),
                    });
                }
                return list;
            };
            act.BeginInvoke((result) =>
            {
                List<VM> dtresult = act.EndInvoke(result);
                this.BeginInvoke(new Action<List<VM>>((List<VM> dtList) =>
                {
                    dataGridView1.DataSource = dtList;
                }), dtresult);
            }, null);