C#中Enterprise Services（微软应用程序服务器）技术(二)

这次我们来看看Enterprise Services的自动事务处理特性，譬如数据库操作时的事务。

每一步的图我就不多贴了，和上一讲大同小异。

先看看工程布局：

先看组件服务端(NorthwindComponent)代码：

OderLineData.cs

#region Using directives using System; using System.Collections.Generic; using System.Text; using System.Data.SqlClient; using System.EnterpriseServices; #endregion namespace Wrox.ProCSharp.EnterpriseServices { public interface IOrderLineUpdate { void Insert(int orderId, OrderLine orderDetail); } [Transaction(TransactionOption.Required)] [EventTrackingEnabled(true)] [ConstructionEnabled(true, Default = "server=localhost;database=northwind;" + "trusted_connection=true")] public class OrderLineData : ServicedComponent, IOrderLineUpdate { private string connectionString = null; protected override void Construct(string s) { connectionString = s; } public void Insert(int orderId, OrderLine orderDetail) { SqlConnection connection = new SqlConnection(connectionString); try { SqlCommand command = connection.CreateCommand(); command.CommandText = "INSERT INTO [Order Details] (OrderId, " + "ProductId, UnitPrice, Quantity)" + "VALUES(@OrderId, @ProductId, @UnitPrice, @Quantity)"; command.Parameters.AddWithValue("@OrderId", orderId); command.Parameters.AddWithValue("@ProductId", orderDetail.ProductId); command.Parameters.AddWithValue("@UnitPrice", orderDetail.UnitPrice); command.Parameters.AddWithValue("@Quantity", orderDetail.Quantity); connection.Open(); command.ExecuteNonQuery(); } catch (Exception) { ContextUtil.SetAbort(); throw; } finally { connection.Close(); } ContextUtil.SetComplete(); } } }

Order.cs

#region Using directives using System; using System.Collections.Generic; using System.Text; #endregion namespace Wrox.ProCSharp.EnterpriseServices { public class Order { public static Order Create(string customerId, DateTime orderDate, string shipAddress, string shipCity, string shipCountry) { Order o = new Order(); o.customerId = customerId; o.orderDate = orderDate; o.shipAddress = shipAddress; o.shipCity = shipCity; o.shipCountry = shipCountry; return o; } public Order() { } internal void SetOrderId(int orderId) { this.orderId = orderId; } public void AddOrderLine(OrderLine orderLine) { orderLines.Add(orderLine); } private int orderId; private string customerId; private DateTime orderDate; private string shipAddress; private string shipCity; private string shipCountry; private List<OrderLine> orderLines = new List<OrderLine>(); public int OrderId { get { return orderId; } } public string CustomerId { get { return customerId; } } public DateTime OrderDate { get { return orderDate; } } public string ShipAddress { get { return shipAddress; } } public string ShipCity { get { return shipCity; } } public string ShipCountry { get { return shipCountry; } } public OrderLine[] OrderLines { get { OrderLine[] ol = new OrderLine[orderLines.Count]; orderLines.CopyTo(ol); return ol; } } } }

OrderControl.cs

#region Using directives using System; using System.Collections.Generic; using System.Text; using System.EnterpriseServices; #endregion [assembly: ApplicationName("Wrox.NorthwindDemo")] [assembly: ApplicationActivation(ActivationOption.Library)] [assembly: ApplicationAccessControl(false)] namespace Wrox.ProCSharp.EnterpriseServices { public interface IOrderControl { void NewOrder(Order order); } [Transaction(TransactionOption.Supported)] [EventTrackingEnabled(true)] public class OrderControl : ServicedComponent, IOrderControl { [AutoComplete()] public void NewOrder(Order order) { OrderData data = new OrderData(); data.Insert(order); } } }

OrderData.cs

#region Using directives using System; using System.Collections.Generic; using System.Text; using System.Data.SqlClient; using System.EnterpriseServices; #endregion namespace Wrox.ProCSharp.EnterpriseServices { public interface IOrderUpdate { void Insert(Order order); } [Transaction(TransactionOption.Required)] [EventTrackingEnabled(true)] [ConstructionEnabled(true, Default="server=localhost;database=northwind;trusted_connection=true")] public class OrderData : ServicedComponent, IOrderUpdate { private string connectionString = null; protected override void Construct(string s) { connectionString = s; } [AutoComplete()] public void Insert(Order order) { SqlConnection connection = new SqlConnection(connectionString); try { SqlCommand command = connection.CreateCommand(); command.CommandText = "INSERT INTO Orders (CustomerId, OrderDate, " + "ShipAddress, ShipCity, ShipCountry)" + "VALUES(@CustomerId, @OrderDate, @ShipAddress, @ShipCity, " + "@ShipCountry)"; command.Parameters.AddWithValue("@CustomerId", order.CustomerId); command.Parameters.AddWithValue("@OrderDate", order.OrderDate); command.Parameters.AddWithValue("@ShipAddress", order.ShipAddress); command.Parameters.AddWithValue("@ShipCity", order.ShipCity); command.Parameters.AddWithValue("@ShipCountry", order.ShipCountry); connection.Open(); command.ExecuteNonQuery(); command.CommandText = "SELECT @@IDENTITY AS 'Identity'"; object identity = command.ExecuteScalar(); order.SetOrderId(Convert.ToInt32(identity)); OrderLineData updateOrderLine = new OrderLineData(); foreach (OrderLine orderLine in order.OrderLines) { updateOrderLine.Insert(order.OrderId, orderLine); } } finally { connection.Close(); } } } }

OrderLine.cs

#region Using directives using System; using System.Collections.Generic; using System.Text; #endregion namespace Wrox.ProCSharp.EnterpriseServices { [Serializable] public class OrderLine { public static OrderLine Create(int productId, float unitPrice, int quantity) { OrderLine detail = new OrderLine(); detail.productId = productId; detail.unitPrice = unitPrice; detail.quantity = quantity; return detail; } public OrderLine() { } private int productId; private float unitPrice; private int quantity; public int ProductId { get { return productId; } set { productId = value; } } public float UnitPrice { get { return unitPrice; } set { unitPrice = value; } } public int Quantity { get { return quantity; } set { quantity = value; } } } }

 

再看客户端（NorthwindClient）代码：

#region Using directives using System; using System.Collections.Generic; using System.Text; using Wrox.ProCSharp.EnterpriseServices; #endregion namespace NorthwindClient { class Program { static void Main(string[] args) { Order order = Order.Create("PICCO", DateTime.Today, "Georg Pipps", "Salzburg", "Austria"); order.AddOrderLine(OrderLine.Create(16, 17.45F, 2)); order.AddOrderLine(OrderLine.Create(67, 14, 1)); using (OrderControl orderControl = new OrderControl()) { orderControl.NewOrder(order); } } } }