佇列可確保客戶端與 Windows Communication Foundation(WCF)服務之間的可靠訊息傳遞,即使服務在通訊時無法使用,仍能進行。 下列程式示範如何在實作 WCF 服務時使用標準佇列系結,確保客戶端與服務之間的持久通訊。
本節說明如何使用 NetMsmqBinding WCF 用戶端與 WCF 服務之間的佇列通訊。
在 WCF 服務中使用佇列
使用標示為的 ServiceContractAttribute介面來定義服務合約。 將 介面中的作業標示為與 OperationContractAttribute 服務合約的一部分,並將它們指定為單向,因為不會傳回方法的回應。 下列程式代碼提供範例服務合約及其作業定義。
[ServiceContract(Namespace="http://Microsoft.ServiceModel.Samples")] public interface IOrderProcessor { [OperationContract(IsOneWay = true)] void SubmitPurchaseOrder(PurchaseOrder po); }
<ServiceContract(Namespace:="http://Microsoft.ServiceModel.Samples")> _ Public Interface IOrderProcessor <OperationContract(IsOneWay:=True)> _ Sub SubmitPurchaseOrder(ByVal po As PurchaseOrder) End Interface
當服務合約傳遞使用者定義型別時,您必須為這些類型定義數據合約。 下列程式代碼顯示兩個資料合約:
PurchaseOrder
和PurchaseOrderLineItem
。 這兩種類型會定義傳送至服務的數據。 (請注意,定義此數據合約的類別也會定義一些方法。這些方法不會被視為數據合約的一部分。只有以 DataMemberAttribute 屬性宣告的成員是數據合約的一部分。[DataContract(Namespace = "http://Microsoft.ServiceModel.Samples")] public class PurchaseOrder { static readonly string[] OrderStates = { "Pending", "Processed", "Shipped" }; static Random statusIndexer = new Random(137); [DataMember] public string PONumber; [DataMember] public string CustomerId; [DataMember] public PurchaseOrderLineItem[] orderLineItems; public float TotalCost { get { float totalCost = 0; foreach (PurchaseOrderLineItem lineItem in orderLineItems) totalCost += lineItem.TotalCost; return totalCost; } } public string Status { get { return OrderStates[statusIndexer.Next(3)]; } } public override string ToString() { System.Text.StringBuilder strbuf = new System.Text.StringBuilder("Purchase Order: " + PONumber + "\n"); strbuf.Append("\tCustomer: " + CustomerId + "\n"); strbuf.Append("\tOrderDetails\n"); foreach (PurchaseOrderLineItem lineItem in orderLineItems) { strbuf.Append("\t\t" + lineItem.ToString()); } strbuf.Append("\tTotal cost of this order: $" + TotalCost + "\n"); strbuf.Append("\tOrder status: " + Status + "\n"); return strbuf.ToString(); } }
<DataContract(Namespace:="http://Microsoft.ServiceModel.Samples")> _ Public Class PurchaseOrder Private Shared ReadOnly OrderStates() As String = {"Pending", "Processed", "Shipped"} Private Shared statusIndexer As New Random(137) <DataMember> _ Public PONumber As String <DataMember> _ Public CustomerId As String <DataMember> _ Public orderLineItems() As PurchaseOrderLineItem Public ReadOnly Property TotalCost() As Single Get Dim totalCost_Renamed As Single = 0 For Each lineItem In orderLineItems totalCost_Renamed += lineItem.TotalCost Next lineItem Return totalCost_Renamed End Get End Property Public ReadOnly Property Status() As String Get Return OrderStates(statusIndexer.Next(3)) End Get End Property Public Overrides Function ToString() As String Dim strbuf As New System.Text.StringBuilder("Purchase Order: " & PONumber & Constants.vbLf) strbuf.Append(Constants.vbTab & "Customer: " & CustomerId & Constants.vbLf) strbuf.Append(Constants.vbTab & "OrderDetails" & Constants.vbLf) For Each lineItem In orderLineItems strbuf.Append(Constants.vbTab + Constants.vbTab + lineItem.ToString()) Next lineItem strbuf.Append(Constants.vbTab & "Total cost of this order: $" & TotalCost + Constants.vbLf) strbuf.Append(Constants.vbTab & "Order status: " & Status + Constants.vbLf) Return strbuf.ToString() End Function End Class
實作 類別中介面中定義的服務合約方法。
public class OrderProcessorService : IOrderProcessor { [OperationBehavior(TransactionScopeRequired = true, TransactionAutoComplete = true)] public void SubmitPurchaseOrder(PurchaseOrder po) { Orders.Add(po); Console.WriteLine($"Processing {po} "); } }
Public Class OrderProcessorService Implements IOrderProcessor <OperationBehavior(TransactionScopeRequired:=True, TransactionAutoComplete:=True)> _ Public Sub SubmitPurchaseOrder(ByVal po As PurchaseOrder) Implements IOrderProcessor.SubmitPurchaseOrder Orders.Add(po) Console.WriteLine("Processing {0} ", po) End Sub End Class
請注意, OperationBehaviorAttribute 被放置在
SubmitPurchaseOrder
方法上。 這會指定必須在交易內呼叫此作業,而且當方法完成時,交易會自動完成。使用 System.Messaging建立交易式佇列。 您可以選擇改為使用 Microsoft 消息佇列 (MSMQ) Microsoft Management Console (MMC) 來建立佇列。 如果是這樣,請確認您建立了交易式佇列。
// Create the transacted MSMQ queue if necessary. if (!MessageQueue.Exists(queueName)) MessageQueue.Create(queueName, true);
' Create the transacted MSMQ queue if necessary. If (Not MessageQueue.Exists(queueName)) Then MessageQueue.Create(queueName, True) End If
把ServiceEndpoint定義在配置中,指定服務位址並使用標準NetMsmqBinding繫結。 如需使用 WCF 組態的詳細資訊,請參閱 設定 WCF 服務。
建立一個使用ServiceHost的主機,用於
OrderProcessing
服務,從佇列讀取訊息並加以處理。 開啟服務主機,讓服務可供使用。 顯示訊息,告知使用者按下任何按鍵來終止服務。 呼叫ReadLine
以等候按下按鍵,然後關閉服務。// Create a ServiceHost for the OrderProcessorService type. using (ServiceHost serviceHost = new ServiceHost(typeof(OrderProcessorService))) { // Open the ServiceHost to create listeners and start listening for messages. serviceHost.Open(); // The service can now be accessed. Console.WriteLine("The service is ready."); Console.WriteLine("Press <ENTER> to terminate service."); Console.WriteLine(); Console.ReadLine(); // Close the ServiceHostB to shutdown the service. serviceHost.Close(); }
' Create a ServiceHost for the OrderProcessorService type. Using serviceHost As New ServiceHost(GetType(OrderProcessorService)) ' Open the ServiceHost to create listeners and start listening for messages. serviceHost.Open() ' The service can now be accessed. Console.WriteLine("The service is ready.") Console.WriteLine("Press <ENTER> to terminate service.") Console.WriteLine() Console.ReadLine() ' Close the ServiceHostB to shutdown the service. serviceHost.Close() End Using
建立佇列服務的客戶端
下列範例示範如何執行主控應用程式,並使用 Svcutil.exe 工具來建立WCF用戶端。
svcutil http://localhost:8000/ServiceModelSamples/service
在組態中定義一個ServiceEndpoint,該設定會指明位址並使用標準NetMsmqBinding系結,如下列範例所示。
建立交易範圍以寫入交易佇列、呼叫
SubmitPurchaseOrder
作業並關閉 WCF 用戶端,如下列範例所示。//Create a transaction scope. using (TransactionScope scope = new TransactionScope(TransactionScopeOption.Required)) { // Make a queued call to submit the purchase order. client.SubmitPurchaseOrder(po); // Complete the transaction. scope.Complete(); } //Closing the client gracefully closes the connection and cleans up resources. client.Close();
'Create a transaction scope. Using scope As New TransactionScope(TransactionScopeOption.Required) ' Make a queued call to submit the purchase order. client.SubmitPurchaseOrder(po) ' Complete the transaction. scope.Complete() End Using 'Closing the client gracefully closes the connection and cleans up resources. client.Close()
範例
下列範例顯示此範例所包含的服務程式代碼、裝載應用程式、App.config 檔案和用戶端程序代碼。
// This is the service code
// Copyright (c) Microsoft Corporation. All Rights Reserved.
using System;
using System.ServiceModel.Channels;
using System.Configuration;
using System.Messaging;
using System.ServiceModel;
using System.Transactions;
using System.Runtime.Serialization;
using System.Collections.Generic;
namespace Microsoft.ServiceModel.Samples
{
// Define the purchase order line item.
[DataContract(Namespace = "http://Microsoft.ServiceModel.Samples")]
public class PurchaseOrderLineItem
{
[DataMember]
public string ProductId;
[DataMember]
public float UnitCost;
[DataMember]
public int Quantity;
public override string ToString()
{
String displayString = "Order LineItem: " + Quantity + " of " + ProductId + " @unit price: $" + UnitCost + "\n";
return displayString;
}
public float TotalCost
{
get { return UnitCost * Quantity; }
}
}
// Define the purchase order.
[DataContract(Namespace = "http://Microsoft.ServiceModel.Samples")]
public class PurchaseOrder
{
static readonly string[] OrderStates = { "Pending", "Processed", "Shipped" };
static Random statusIndexer = new Random(137);
[DataMember]
public string PONumber;
[DataMember]
public string CustomerId;
[DataMember]
public PurchaseOrderLineItem[] orderLineItems;
public float TotalCost
{
get
{
float totalCost = 0;
foreach (PurchaseOrderLineItem lineItem in orderLineItems)
totalCost += lineItem.TotalCost;
return totalCost;
}
}
public string Status
{
get
{
return OrderStates[statusIndexer.Next(3)];
}
}
public override string ToString()
{
System.Text.StringBuilder strbuf = new System.Text.StringBuilder("Purchase Order: " + PONumber + "\n");
strbuf.Append("\tCustomer: " + CustomerId + "\n");
strbuf.Append("\tOrderDetails\n");
foreach (PurchaseOrderLineItem lineItem in orderLineItems)
{
strbuf.Append("\t\t" + lineItem.ToString());
}
strbuf.Append("\tTotal cost of this order: $" + TotalCost + "\n");
strbuf.Append("\tOrder status: " + Status + "\n");
return strbuf.ToString();
}
}
// Order Processing Logic
// Can replace with transaction-aware resource such as SQL or transacted hashtable to hold the purchase orders.
// This example uses a non-transactional resource.
public class Orders
{
static Dictionary<string, PurchaseOrder> purchaseOrders = new Dictionary<string, PurchaseOrder>();
public static void Add(PurchaseOrder po)
{
purchaseOrders.Add(po.PONumber, po);
}
public static string GetOrderStatus(string poNumber)
{
PurchaseOrder po;
if (purchaseOrders.TryGetValue(poNumber, out po))
return po.Status;
else
return null;
}
public static void DeleteOrder(string poNumber)
{
if(purchaseOrders[poNumber] != null)
purchaseOrders.Remove(poNumber);
}
}
// Define a service contract.
[ServiceContract(Namespace="http://Microsoft.ServiceModel.Samples")]
public interface IOrderProcessor
{
[OperationContract(IsOneWay = true)]
void SubmitPurchaseOrder(PurchaseOrder po);
}
// Service class that implements the service contract.
// Added code to write output to the console window.
public class OrderProcessorService : IOrderProcessor
{
[OperationBehavior(TransactionScopeRequired = true, TransactionAutoComplete = true)]
public void SubmitPurchaseOrder(PurchaseOrder po)
{
Orders.Add(po);
Console.WriteLine($"Processing {po} ");
}
}
}
' This is the service code
' Copyright (c) Microsoft Corporation. All Rights Reserved.
Imports System.ServiceModel.Channels
Imports System.Configuration
Imports System.Messaging
Imports System.ServiceModel
Imports System.Transactions
Imports System.Runtime.Serialization
Imports System.Collections.Generic
Namespace Microsoft.ServiceModel.Samples
' Define the purchase order line item.
<DataContract(Namespace:="http://Microsoft.ServiceModel.Samples")> _
Public Class PurchaseOrderLineItem
<DataMember> _
Public ProductId As String
<DataMember> _
Public UnitCost As Single
<DataMember> _
Public Quantity As Integer
Public Overrides Function ToString() As String
Dim displayString As String = "Order LineItem: " & Quantity & " of " & ProductId & " @unit price: $" & UnitCost + Constants.vbLf
Return displayString
End Function
Public ReadOnly Property TotalCost() As Single
Get
Return UnitCost * Quantity
End Get
End Property
End Class
' Define the purchase order.
<DataContract(Namespace:="http://Microsoft.ServiceModel.Samples")> _
Public Class PurchaseOrder
Private Shared ReadOnly OrderStates() As String = {"Pending", "Processed", "Shipped"}
Private Shared statusIndexer As New Random(137)
<DataMember> _
Public PONumber As String
<DataMember> _
Public CustomerId As String
<DataMember> _
Public orderLineItems() As PurchaseOrderLineItem
Public ReadOnly Property TotalCost() As Single
Get
Dim totalCost_Renamed As Single = 0
For Each lineItem In orderLineItems
totalCost_Renamed += lineItem.TotalCost
Next lineItem
Return totalCost_Renamed
End Get
End Property
Public ReadOnly Property Status() As String
Get
Return OrderStates(statusIndexer.Next(3))
End Get
End Property
Public Overrides Function ToString() As String
Dim strbuf As New System.Text.StringBuilder("Purchase Order: " & PONumber & Constants.vbLf)
strbuf.Append(Constants.vbTab & "Customer: " & CustomerId & Constants.vbLf)
strbuf.Append(Constants.vbTab & "OrderDetails" & Constants.vbLf)
For Each lineItem In orderLineItems
strbuf.Append(Constants.vbTab + Constants.vbTab + lineItem.ToString())
Next lineItem
strbuf.Append(Constants.vbTab & "Total cost of this order: $" & TotalCost + Constants.vbLf)
strbuf.Append(Constants.vbTab & "Order status: " & Status + Constants.vbLf)
Return strbuf.ToString()
End Function
End Class
' Order Processing Logic
' Can replace with transaction-aware resource such as SQL or transacted hashtable to hold the purchase orders.
' This example uses a non-transactional resource.
Public Class Orders
Private Shared purchaseOrders As New Dictionary(Of String, PurchaseOrder)()
Public Shared Sub Add(ByVal po As PurchaseOrder)
purchaseOrders.Add(po.PONumber, po)
End Sub
Public Shared Function GetOrderStatus(ByVal poNumber As String) As String
Dim po As PurchaseOrder = Nothing
If purchaseOrders.TryGetValue(poNumber, po) Then
Return po.Status
Else
Return Nothing
End If
End Function
Public Shared Sub DeleteOrder(ByVal poNumber As String)
If purchaseOrders(poNumber) IsNot Nothing Then
purchaseOrders.Remove(poNumber)
End If
End Sub
End Class
' Define a service contract.
<ServiceContract(Namespace:="http://Microsoft.ServiceModel.Samples")> _
Public Interface IOrderProcessor
<OperationContract(IsOneWay:=True)> _
Sub SubmitPurchaseOrder(ByVal po As PurchaseOrder)
End Interface
' Service class that implements the service contract.
' Added code to write output to the console window.
Public Class OrderProcessorService
Implements IOrderProcessor
<OperationBehavior(TransactionScopeRequired:=True, TransactionAutoComplete:=True)> _
Public Sub SubmitPurchaseOrder(ByVal po As PurchaseOrder) Implements IOrderProcessor.SubmitPurchaseOrder
Orders.Add(po)
Console.WriteLine("Processing {0} ", po)
End Sub
End Class
End Namespace
// This is the hosting application.
using System;
using System.ServiceModel.Channels;
using System.Configuration;
using System.Messaging;
using System.ServiceModel;
using System.Transactions;
using System.Runtime.Serialization;
using System.Collections.Generic;
namespace Microsoft.ServiceModel.Samples
{
class hostApp
{
// Host the service within this EXE console application.
public static void Main()
{
// Get MSMQ queue name from appsettings in configuration.
string queueName = ConfigurationManager.AppSettings["queueName"];
// Create the transacted MSMQ queue if necessary.
if (!MessageQueue.Exists(queueName))
MessageQueue.Create(queueName, true);
// Create a ServiceHost for the OrderProcessorService type.
using (ServiceHost serviceHost = new ServiceHost(typeof(OrderProcessorService)))
{
// Open the ServiceHost to create listeners and start listening for messages.
serviceHost.Open();
// The service can now be accessed.
Console.WriteLine("The service is ready.");
Console.WriteLine("Press <ENTER> to terminate service.");
Console.WriteLine();
Console.ReadLine();
// Close the ServiceHostB to shutdown the service.
serviceHost.Close();
}
}
}
}
' This is the hosting application.
Imports System.ServiceModel.Channels
Imports System.Configuration
Imports System.Messaging
Imports System.ServiceModel
Imports System.Transactions
Imports System.Runtime.Serialization
Imports System.Collections.Generic
Namespace Microsoft.ServiceModel.Samples
Friend Class hostApp
' Host the service within this EXE console application.
Public Shared Sub Main()
' Get MSMQ queue name from appsettings in configuration.
Dim queueName As String = ConfigurationManager.AppSettings("queueName")
' Create the transacted MSMQ queue if necessary.
If (Not MessageQueue.Exists(queueName)) Then
MessageQueue.Create(queueName, True)
End If
' Create a ServiceHost for the OrderProcessorService type.
Using serviceHost As New ServiceHost(GetType(OrderProcessorService))
' Open the ServiceHost to create listeners and start listening for messages.
serviceHost.Open()
' The service can now be accessed.
Console.WriteLine("The service is ready.")
Console.WriteLine("Press <ENTER> to terminate service.")
Console.WriteLine()
Console.ReadLine()
' Close the ServiceHostB to shutdown the service.
serviceHost.Close()
End Using
End Sub
End Class
End Namespace
// This is the client code.
// Copyright (c) Microsoft Corporation. All Rights Reserved.
using System;
using System.Configuration;
using System.Messaging;
using System.ServiceModel;
using System.Transactions;
namespace Microsoft.ServiceModel.Samples
{
//The service contract is defined in generatedClient.cs, generated from the service by the svcutil tool.
//Client implementation code.
class Client
{
static void Main()
{
// Create a client.
OrderProcessorClient client = new OrderProcessorClient();
// Create the purchase order.
PurchaseOrder po = new PurchaseOrder();
po.CustomerId = "somecustomer.com";
po.PONumber = Guid.NewGuid().ToString();
PurchaseOrderLineItem lineItem1 = new PurchaseOrderLineItem();
lineItem1.ProductId = "Blue Widget";
lineItem1.Quantity = 54;
lineItem1.UnitCost = 29.99F;
PurchaseOrderLineItem lineItem2 = new PurchaseOrderLineItem();
lineItem2.ProductId = "Red Widget";
lineItem2.Quantity = 890;
lineItem2.UnitCost = 45.89F;
po.orderLineItems = new PurchaseOrderLineItem[2];
po.orderLineItems[0] = lineItem1;
po.orderLineItems[1] = lineItem2;
//Create a transaction scope.
using (TransactionScope scope = new TransactionScope(TransactionScopeOption.Required))
{
// Make a queued call to submit the purchase order.
client.SubmitPurchaseOrder(po);
// Complete the transaction.
scope.Complete();
}
//Closing the client gracefully closes the connection and cleans up resources.
client.Close();
Console.WriteLine();
Console.WriteLine("Press <ENTER> to terminate client.");
Console.ReadLine();
}
}
}
' This is the client code.
' Copyright (c) Microsoft Corporation. All Rights Reserved.
Imports System.Configuration
Imports System.Messaging
Imports System.ServiceModel
Imports System.Transactions
Namespace Microsoft.ServiceModel.Samples
'The service contract is defined in generatedClient.cs, generated from the service by the svcutil tool.
'Client implementation code.
Friend Class Client
Shared Sub Main()
' Create a client.
Dim client As New OrderProcessorClient()
' Create the purchase order.
Dim po As New PurchaseOrder()
po.CustomerId = "somecustomer.com"
po.PONumber = Guid.NewGuid().ToString()
Dim lineItem1 As New PurchaseOrderLineItem()
lineItem1.ProductId = "Blue Widget"
lineItem1.Quantity = 54
lineItem1.UnitCost = 29.99F
Dim lineItem2 As New PurchaseOrderLineItem()
lineItem2.ProductId = "Red Widget"
lineItem2.Quantity = 890
lineItem2.UnitCost = 45.89F
po.orderLineItems = New PurchaseOrderLineItem(1) {}
po.orderLineItems(0) = lineItem1
po.orderLineItems(1) = lineItem2
'Create a transaction scope.
Using scope As New TransactionScope(TransactionScopeOption.Required)
' Make a queued call to submit the purchase order.
client.SubmitPurchaseOrder(po)
' Complete the transaction.
scope.Complete()
End Using
'Closing the client gracefully closes the connection and cleans up resources.
client.Close()
Console.WriteLine()
Console.WriteLine("Press <ENTER> to terminate client.")
Console.ReadLine()
End Sub
End Class
End Namespace