// 按ID查询// 按客户查询//按数量查询//按商品查询//查询全部 private void querybutton_Click(object sender, EventArgs e) { Console.WriteLine(this.message); switch (Query_Way) { case "按ID查询": this.orderbindingSource.DataSource = service.GetById(Convert.ToInt32(message)); if (service.GetById(Convert.ToInt32(message)) != null) { this.detailbindingSource.DataSource = service.GetById(Convert.ToInt32(message)).Details; } else { this.detailbindingSource.DataSource = null; } break; case "按客户查询": this.orderbindingSource.DataSource = service.QueryByCustomerName(message); break; case "按数量查询": this.orderbindingSource.DataSource = service.QueryByTotalAmount(Convert.ToDouble(message)); break; case "按商品查询": this.orderbindingSource.DataSource = service.QueryByGoodsName(message); break; case "查询全部": this.orderbindingSource.DataSource = service.QueryAll(); break; default: break; } if (Query_Way != "按ID查询") { List <ordertest.Order> o = (List <ordertest.Order>)orderbindingSource.DataSource; List <ordertest.OrderDetail> de = new List <ordertest.OrderDetail>(); if (o != null) { foreach (var i in o) { List <ordertest.OrderDetail> p = i.Details; foreach (var j in p) { de.Add(j); } } detailbindingSource.DataSource = de; } } }