一,回顾
上一部分讲述了“在ADO.NET中利用DataTable对象,将其作为参数传给存贮过程”。
通过DataTable实例,完成了两部分的内容:
1)DataTable的数据传输给Stored Procedure
2)利用DataTable的TVP数据,可以参与别的实体数据读写(DataReader)。
这一部分的内容,通过Collection对象,还是要实现上边的两个实例。
二,在ADO.NET中利用Collection对象,将其作为参数传给存贮过程
通过实例,大家对各个特性和参数的如何使用,有更深刻的感性认识。同时,通过
这些实例的改造,也可做出符合自己的程序代码。
这次,还是主要输出Sample,包含两部分的内容:
1)DataTable的数据传输给Stored Procedure
2)利用DataTable的TVP数据,可以参与别的实体数据读写(DataReader)。
具体实例如下:
//---Main Sub private void btnCollection_Click(object sender, EventArgs e) { //------利用OrderItem object List<OrderItem> orderItems = new List<OrderItem>(); orderItems.Add(new OrderItem() { OrderId = 901, CustomerId = 67, OrderedAt = DateTime.Now }); orderItems.Add(new OrderItem() { OrderId = 902, CustomerId = 68, OrderedAt = DateTime.Now }); OrderItemCollection itemCollection = new OrderItemCollection(); itemCollection.AddRange(orderItems); //------利用OrderDetail object List<OrderDetail> orderDetails = new List<OrderDetail>(); orderDetails.Add(new OrderDetail() { OrderId = 901, LineNumber = 1, ProductId = 34, Quantity = 2, Price = 10.5m }); orderDetails.Add(new OrderDetail() { OrderId = 901, LineNumber = 2, ProductId = 100, Quantity = 45, Price = 3.8m }); orderDetails.Add(new OrderDetail() { OrderId = 901, LineNumber = 3, ProductId = 56, Quantity = 67, Price = 9.1m }); orderDetails.Add(new OrderDetail() { OrderId = 902, LineNumber = 1, ProductId = 88, Quantity = 5, Price = 88.5m }); orderDetails.Add(new OrderDetail() { OrderId = 902, LineNumber = 2, ProductId = 1, Quantity = 345, Price = 0.465m }); OrderDetailCollection detailCollection = new OrderDetailCollection(); detailCollection.AddRange(orderDetails); //---- using (SqlConnection conn = new SqlConnection("Data Source=;Initial Catalog=AdventureWorks;User ID=sa;Password=")) { conn.Open(); //---Passing a Table-Valued Parameter to a Stored Pcocedure using (SqlCommand cmd = new SqlCommand("dbo.OrderItem$Insert", conn)) { cmd.CommandType = CommandType.StoredProcedure; //---注意:下边的两个参数名,要和SP的参数名一致。 SqlParameter tvpOrderItem = cmd.Parameters.AddWithValue("@OrderHeaders", itemCollection); SqlParameter tvpOrderDetail = cmd.Parameters.AddWithValue("@OrderDetails", detailCollection); tvpOrderItem.SqlDbType = SqlDbType.Structured; tvpOrderDetail.SqlDbType = SqlDbType.Structured; cmd.ExecuteNonQuery(); } //---Streadming rows with a dataReader string sql = @"select tvp1.OrderId, tvp1.CustomerId, tvp2.LineNumber, tvp2.ProductId from dbo.OrderItem as tvp1 INNER JOIN @tvpDetail as tvp2 ON tvp1.OrderId=tvp2.OrderId order by tvp2.OrderId, tvp2.LineNumber;"; SqlCommand readCommand = new SqlCommand(sql, conn); readCommand.CommandType = CommandType.Text; SqlParameter tvpDetail = readCommand.Parameters.AddWithValue("@tvpDetail", detailCollection); tvpDetail.SqlDbType = SqlDbType.Structured; tvpDetail.TypeName = "dbo.OrderDetail$Udt"; SqlDataReader reader = readCommand.ExecuteReader(); while (reader.Read()) { Console.WriteLine(string.Format("OrderId={0}, CustomrId={1}, LineNumber={2}, ProductId={3}", reader.GetInt32(0), reader.GetInt32(1), reader.GetInt32(2), reader.GetInt32(3))); } reader.Close(); // Output results: //------------------ //OrderId=901, CustomrId=67, LineNumber=1, ProductId=34 //OrderId=901, CustomrId=67, LineNumber=2, ProductId=100 //OrderId=901, CustomrId=67, LineNumber=3, ProductId=56 //OrderId=902, CustomrId=68, LineNumber=1, ProductId=88 //OrderId=902, CustomrId=68, LineNumber=2, ProductId=1 //------------------ conn.Close(); } } //---OrderItem object public sealed class OrderItem { public int OrderId { get; set; } public int CustomerId { get; set; } public DateTime OrderedAt { get; set; } } //---OrderDetail object public sealed class OrderDetail { public int OrderId { get; set; } public int LineNumber { get; set; } public int ProductId { get; set; } public int Quantity { get; set; } public decimal Price { get; set; } } //---OrderItemCollection public sealed class OrderItemCollection: List<OrderItem>, IEnumerable<SqlDataRecord> { #region IEnumerable<SqlDataRecord> Members public new IEnumerator<SqlDataRecord> GetEnumerator() { SqlDataRecord record = new SqlDataRecord( new SqlMetaData("OrderId", SqlDbType.Int), new SqlMetaData("CustomerId", SqlDbType.Int), new SqlMetaData("OrderedAt", SqlDbType.DateTime)); foreach(OrderItem item in this.ToArray()) { record.SetInt32(0, item.OrderId); record.SetInt32(1, item.CustomerId); record.SetDateTime(2, item.OrderedAt); yield return record; } } #endregion } //---OrderDetailCollection public sealed class OrderDetailCollection: List<OrderDetail>, IEnumerable<SqlDataRecord> { #region IEnumerable<SqlDataRecord> Members public new IEnumerator<SqlDataRecord> GetEnumerator() { SqlDataRecord record = new SqlDataRecord( new SqlMetaData("OrderId", SqlDbType.Int), new SqlMetaData("LineNumber", SqlDbType.Int), new SqlMetaData("ProductId", SqlDbType.Int), new SqlMetaData("Quantity", SqlDbType.Int), new SqlMetaData("Price", SqlDbType.Money)); foreach (OrderDetail detail in this.ToArray()) { record.SetInt32(0, detail.OrderId); record.SetInt32(1, detail.LineNumber); record.SetInt32(2, detail.ProductId); record.SetInt32(3, detail.Quantity); record.SetDecimal(4, detail.Price); yield return record; } } #endregion }
三,其他
通过Table-Values三部分的内容描述和实例,相信大家对TVP的应用有了一定的了解。
在编程中也许有人还是习惯在插入多项或Select多行数据时,使用笨拙的逗号分隔列表或XML,
虽其能够胜任,但不是以习惯的对象方式存在,而且存取速度也很慢。
所以,我建议大家在使用IN语句等需要发送多行数据的编程时,多考虑使用TVP的方式,会取满意的效果。
关于这方面的内容,还需要大家不断的交流和探讨。
四,参考文档
参看URL:
ms-help://MS.SQLCC.v10/MS.SQLSVR.v10.en/s10de_1devconc/html/5e95a382-1e01-4c74-81f5-055612c2ad99.htm
ms-help://MS.MSDNQTR.v90.en/wd_adonet/html/370c16d5-db7b-43e3-945b-ccaab35b739b.htm