WCF 实例模式和对象生命周期

1、WCF 几种服务对象实例创建模式

wcf中有三种服务对象实例创建模式：PerCall、PerSession、Single.(具体在哪里设置，最后例子中有很好的阐述)

2、几种模式下服务对象实例的生命周期(这里暂不考虑Mep)

PerCall模式

PerCall模式工作流程如下

客户端创建代理对象(Proxy)
客户端调用代理对象的一个契约操作,代理对象将其传递给服务宿主程序
宿主应用程序创建一新的服务契约对象，并且执行请求操作
在执行完请求操作后，如果要求有应答，那么服务契约会给代理对象一个应答，然后销毁自己

示例代码展示

服务契约代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ServiceModel;

namespace Contract
{
    [ServiceContract(Name="CalculatorService",Namespace="http://www/gxs.com")]
    public interface ICalculator:IDisposable
    {
        [OperationContract(Name = "CalculatorAdd")]
        double Add(double x, double y);
        [OperationContract(Name = "CalculatorSubtract")]
        double Subtract(double x, double y);
    }
}

服务代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Contract;
using System.ServiceModel;

namespace Service
{
    [ServiceBehavior(InstanceContextMode = InstanceContextMode.PerCall)]
    public class CalculatorPerCall:ICalculator
    {
        public CalculatorPerCall()
        {
            Console.WriteLine("Create a new instance!!!");
        }
        public double Add(double x, double y)
        {
            Console.WriteLine("Call [Add] Method");
            return x + y;
        }
        public double Subtract(double x, double y)
        {
            Console.WriteLine("Call [Subtract] Method");
            return x - y;
        }
        public void Dispose()
        {
            Console.WriteLine("The instance has been disposed!!!");
        }
    }
}

服务端宿主代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ServiceModel;
using Contract;
using Service;
using System.ServiceModel.Description;

namespace Hosting
{
    class Program
    {
        static void Main(string[] args)
        {
            using (ServiceHost host = new ServiceHost(typeof(CalculatorPerCall)))
            {
                host.AddServiceEndpoint(typeof(ICalculator), new WSHttpBinding(), "http://127.0.0.1:8089/CalculatorService");
                //ServiceMetadataBehavior:控制服务元数据和相关信息的发布
                if (host.Description.Behaviors.Find<ServiceMetadataBehavior>() == null)
                {
                    ServiceMetadataBehavior behavior = new ServiceMetadataBehavior();
                    behavior.HttpGetEnabled = true;
                    behavior.HttpGetUrl = new Uri("http://127.0.0.1:8089/CalculatorService/metadata");
                    host.Description.Behaviors.Add(behavior);
                }
                host.Opened += new EventHandler(host_Opened);
                host.Open();
                Console.Read();
            }
        }

        static void host_Opened(object sender, EventArgs e)
        {
            Console.WriteLine("计算机服务已经被打开了......");
        }
    }
}

客户端代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace WcfLifeCycle.Client
{
    /// <summary>
    /// wcf实例模型
    /// </summary>
    public class ClientCalculator
    {
        public static void Main(string[] args)
        {
            CalculatorServiceClient proxy1 = new CalculatorServiceClient();
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            Console.WriteLine("******************************************");
            CalculatorServiceClient proxy2= new CalculatorServiceClient();
            Console.WriteLine("proxy2 Call [Add] method");
            proxy2.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy2 Call [Add] method");
            proxy2.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy2 Call [Add] method");
            proxy2.CalculatorAdd(12d, 13d);
            Console.Read();
        }
    }
}

结果示例图

服务端：

客户端

小结：Percall模式，客户端每次发出请求后，服务端都会生成一个实例响应，响应完毕后自行销毁。

PerSession模式

PerSession模式工作的流程如下：

客户端创建代理对象(Proxy)
客户端第一次调用代理对象的一个契约操作，代理对象将其调用请求传递给服务宿主
宿主程序创建新的服务对象，并执行请求操作，如果有必要，返回客户端应答
客户端再次发出调用操作的请求（图中的proxy一与服务实例一对应，proxy二与服务实例二对应），宿主会先判断是否已有建立好的会话，如果存在，则不需要再创建新的服务对象，直接使用老对象即可，如果不存在则新建一个服务对象。
在时间达到指定要求或者因一些特殊原因，会话会过期，此时服务对象销毁.或者客户端关闭，服务对象也会自动销毁。

示例代码展示

服务契约代码如下：

View Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ServiceModel;

namespace Contract
{
    [ServiceContract(Name="CalculatorService",Namespace="http://www/gxs.com")]
    public interface ICalculator:IDisposable
    {
        [OperationContract(Name = "CalculatorAdd")]
        double Add(double x, double y);
        [OperationContract(Name = "CalculatorSubtract")]
        double Subtract(double x, double y);
    }
}

服务代码如下：

View Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Contract;
using System.ServiceModel;

namespace Service
{
    [ServiceBehavior(InstanceContextMode = InstanceContextMode.PerSession)]
    public class CalculatorPerSession : ICalculator
    {
        public CalculatorPerSession()
        {
            Console.WriteLine("Create a new instance!!!");
        }
        public double Add(double x, double y)
        {
            Console.WriteLine("Call [Add] Method");
            return x + y;
        }
        public double Subtract(double x, double y)
        {
            Console.WriteLine("Call [Subtract] Method");
            return x - y;
        }
        public void Dispose()
        {
            Console.WriteLine("The instance has been disposed!!!");
        }
    }
}

服务端宿主代码

View Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ServiceModel;
using Contract;
using Service;
using System.ServiceModel.Description;

namespace Hosting
{
    class Program
    {
        static void Main(string[] args)
        {
            using (ServiceHost host = new ServiceHost(typeof(CalculatorPerSession)))
            {
                host.AddServiceEndpoint(typeof(ICalculator), new WSHttpBinding(), "http://127.0.0.1:8089/CalculatorService");
                //ServiceMetadataBehavior:控制服务元数据和相关信息的发布
                if (host.Description.Behaviors.Find<ServiceMetadataBehavior>() == null)
                {
                    ServiceMetadataBehavior behavior = new ServiceMetadataBehavior();
                    behavior.HttpGetEnabled = true;
                    behavior.HttpGetUrl = new Uri("http://127.0.0.1:8089/CalculatorService/metadata");
                    host.Description.Behaviors.Add(behavior);
                }
                host.Opened += new EventHandler(host_Opened);
                host.Open();
                Console.Read();
            }
        }
        static void host_Opened(object sender, EventArgs e)
        {
            Console.WriteLine("计算机服务已经被打开了......");
        }
    }
}

客户端代码如下：

View Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace WcfLifeCycle.Client
{
    /// <summary>
    /// wcf实例模型
    /// </summary>
    public class ClientCalculator
    {
        public static void Main(string[] args)
        {
            CalculatorServiceClient proxy1 = new CalculatorServiceClient();
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            Console.WriteLine("******************************************");
            CalculatorServiceClient proxy2= new CalculatorServiceClient();
            Console.WriteLine("proxy2 Call [Add] method");
            proxy2.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy2 Call [Add] method");
            proxy2.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy2 Call [Add] method");
            proxy2.CalculatorAdd(12d, 13d);
            Console.Read();
        }
    }
}

结果实例图

服务端

客户端

小结：PerSession模式，proxy与服务实例对应。不同的proxy有不同的服务实例。

Single模式

Single模式的工作流程如下：

服务端启动，同时创建服务对象
客户端通过代理调用契约操作
第一步中创建的服务对象接受请求，并执行操作，进行必要的应答
第一步创建的服务对象将一直保留
服务关闭，第一步创建的对象销毁

示例代码展示：

服务契约代码

View Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ServiceModel;

namespace Contract
{
    [ServiceContract(Name="CalculatorService",Namespace="http://www/gxs.com")]
    public interface ICalculator:IDisposable
    {
        [OperationContract(Name = "CalculatorAdd")]
        double Add(double x, double y);
        [OperationContract(Name = "CalculatorSubtract")]
        double Subtract(double x, double y);
    }
}

服务代码

View Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Contract;
using System.ServiceModel;

namespace Service
{
    [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
    public class CalculatorPerSingle : ICalculator
    {
        public CalculatorPerSingle()
        {
            Console.WriteLine("Create a new instance!!!");
        }
        public double Add(double x, double y)
        {
            Console.WriteLine("Call [Add] Method");
            return x + y;
        }
        public double Subtract(double x, double y)
        {
            Console.WriteLine("Call [Subtract] Method");
            return x - y;
        }
        public void Dispose()
        {
            Console.WriteLine("The instance has been disposed!!!");
        }
    }
}

服务端宿主代码

View Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ServiceModel;
using Contract;
using Service;
using System.ServiceModel.Description;

namespace Hosting
{
    class Program
    {
        static void Main(string[] args)
        {
            using (ServiceHost host = new ServiceHost(typeof(CalculatorPerSingle), new Uri("http://127.0.0.1:8089")))
            {
                host.AddServiceEndpoint(typeof(ICalculator), new WSHttpBinding(), "CalculatorServiceOne");
                host.AddServiceEndpoint(typeof(ICalculator), new WSHttpBinding(), "CalculatorServiceTwo");
                //ServiceMetadataBehavior:控制服务元数据和相关信息的发布
                if (host.Description.Behaviors.Find<ServiceMetadataBehavior>() == null)
                {
                    ServiceMetadataBehavior behavior = new ServiceMetadataBehavior();
                    behavior.HttpGetEnabled = true;
                    behavior.HttpGetUrl = new Uri("http://127.0.0.1:8089/CalculatorService/metadata");
                    host.Description.Behaviors.Add(behavior);
                }
                host.Opened += new EventHandler(host_Opened);
                host.Open();
                Console.Read();
            }
        }
        static void host_Opened(object sender, EventArgs e)
        {
            Console.WriteLine("计算机服务已经被打开了......");
        }
    }
}

客户端一代码

View Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace WcfLifeCycle.Client
{
    /// <summary>
    /// wcf实例模型
    /// </summary>
    public class ClientOneCalculator
    {
        public static void Main(string[] args)
        {
            CalculatorServiceClient proxy1 = new CalculatorServiceClient("WSHttpBinding_CalculatorService");
            Console.WriteLine("I am EndPointOne");
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            proxy1.Close();
            Console.Read();
        }
    }
}

客户端一配置文件app.config

View Code

<?xml version="1.0"?>
<configuration>
    <system.serviceModel>
        <bindings>
            <wsHttpBinding>
                <binding name="WSHttpBinding_CalculatorService" closeTimeout="00:01:00"
                    openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00"
                    bypassProxyOnLocal="false" transactionFlow="false" hostNameComparisonMode="StrongWildcard"
                    maxBufferPoolSize="524288" maxReceivedMessageSize="65536"
                    messageEncoding="Text" textEncoding="utf-8" useDefaultWebProxy="true"
                    allowCookies="false">
                    <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384"
                        maxBytesPerRead="4096" maxNameTableCharCount="16384" />
                    <reliableSession ordered="true" inactivityTimeout="00:10:00"
                        enabled="false" />
                    <security mode="Message">
                        <transport clientCredentialType="Windows" proxyCredentialType="None"
                            realm="" />
                        <message clientCredentialType="Windows" negotiateServiceCredential="true"
                            algorithmSuite="Default" />
                    </security>
                </binding>
                <binding name="WSHttpBinding_CalculatorService1" closeTimeout="00:01:00"
                    openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00"
                    bypassProxyOnLocal="false" transactionFlow="false" hostNameComparisonMode="StrongWildcard"
                    maxBufferPoolSize="524288" maxReceivedMessageSize="65536"
                    messageEncoding="Text" textEncoding="utf-8" useDefaultWebProxy="true"
                    allowCookies="false">
                    <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384"
                        maxBytesPerRead="4096" maxNameTableCharCount="16384" />
                    <reliableSession ordered="true" inactivityTimeout="00:10:00"
                        enabled="false" />
                    <security mode="Message">
                        <transport clientCredentialType="Windows" proxyCredentialType="None"
                            realm="" />
                        <message clientCredentialType="Windows" negotiateServiceCredential="true"
                            algorithmSuite="Default" />
                    </security>
                </binding>
            </wsHttpBinding>
        </bindings>
        <client>
            <endpoint address="http://127.0.0.1:8089/CalculatorServiceOne"
                binding="wsHttpBinding" bindingConfiguration="WSHttpBinding_CalculatorService"
                contract="Client.CalculatorService" name="WSHttpBinding_CalculatorService">
                <identity>
                    <userPrincipalName value="guxiaoshi-PC\guxiaoshi" />
                </identity>
            </endpoint>
            <endpoint address="http://127.0.0.1:8089/CalculatorServiceTwo"
                binding="wsHttpBinding" bindingConfiguration="WSHttpBinding_CalculatorService1"
                contract="Client.CalculatorService" name="WSHttpBinding_CalculatorService1">
                <identity>
                    <userPrincipalName value="guxiaoshi-PC\guxiaoshi" />
                </identity>
            </endpoint>
        </client>
    </system.serviceModel>
<startup><supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/></startup></configuration>

客户端二代码

View Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using ClientTwo.Client;

namespace ClientTwo
{
    class ClientTwoCalculator
    {
        static void Main(string[] args)
        {
            CalculatorServiceClient proxy1 = new CalculatorServiceClient("WSHttpBinding_CalculatorService1");
            Console.WriteLine("I am EndPointTwo");
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            Console.WriteLine("proxy1 Call [Add] method");
            proxy1.CalculatorAdd(12d, 13d);
            proxy1.Close();
            Console.Read();
        }
    }
}

客户端二配置文件app.config

View Code

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <system.serviceModel>
        <bindings>
            <wsHttpBinding>
                <binding name="WSHttpBinding_CalculatorService" closeTimeout="00:01:00"
                    openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00"
                    bypassProxyOnLocal="false" transactionFlow="false" hostNameComparisonMode="StrongWildcard"
                    maxBufferPoolSize="524288" maxReceivedMessageSize="65536"
                    messageEncoding="Text" textEncoding="utf-8" useDefaultWebProxy="true"
                    allowCookies="false">
                    <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384"
                        maxBytesPerRead="4096" maxNameTableCharCount="16384" />
                    <reliableSession ordered="true" inactivityTimeout="00:10:00"
                        enabled="false" />
                    <security mode="Message">
                        <transport clientCredentialType="Windows" proxyCredentialType="None"
                            realm="" />
                        <message clientCredentialType="Windows" negotiateServiceCredential="true"
                            algorithmSuite="Default" />
                    </security>
                </binding>
                <binding name="WSHttpBinding_CalculatorService1" closeTimeout="00:01:00"
                    openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00"
                    bypassProxyOnLocal="false" transactionFlow="false" hostNameComparisonMode="StrongWildcard"
                    maxBufferPoolSize="524288" maxReceivedMessageSize="65536"
                    messageEncoding="Text" textEncoding="utf-8" useDefaultWebProxy="true"
                    allowCookies="false">
                    <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384"
                        maxBytesPerRead="4096" maxNameTableCharCount="16384" />
                    <reliableSession ordered="true" inactivityTimeout="00:10:00"
                        enabled="false" />
                    <security mode="Message">
                        <transport clientCredentialType="Windows" proxyCredentialType="None"
                            realm="" />
                        <message clientCredentialType="Windows" negotiateServiceCredential="true"
                            algorithmSuite="Default" />
                    </security>
                </binding>
            </wsHttpBinding>
        </bindings>
        <client>
            <endpoint address="http://127.0.0.1:8089/CalculatorServiceOne"
                binding="wsHttpBinding" bindingConfiguration="WSHttpBinding_CalculatorService"
                contract="Client.CalculatorService" name="WSHttpBinding_CalculatorService">
                <identity>
                    <userPrincipalName value="guxiaoshi-PC\guxiaoshi" />
                </identity>
            </endpoint>
            <endpoint address="http://127.0.0.1:8089/CalculatorServiceTwo"
                binding="wsHttpBinding" bindingConfiguration="WSHttpBinding_CalculatorService1"
                contract="Client.CalculatorService" name="WSHttpBinding_CalculatorService1">
                <identity>
                    <userPrincipalName value="guxiaoshi-PC\guxiaoshi" />
                </identity>
            </endpoint>
        </client>
    </system.serviceModel>
</configuration>

结果实例图

服务端

客户端一

客户端二

小结：服务端自始至终只有一个实例与客户端进行消息的交换。

总结：上文是对服务对象实例生命周期的介绍.Percall:新的请求产生新的服务对象与之交换信息，服务对象自行销毁；PerSession：相同的客户端由同一个服务对象与之交换信息(这里的客户端指proxy)；Single:服务端只有一个服务实例，服务打开时服务实例就会被创建。

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原文地址：https://www.cnblogs.com/smallstone/p/2277194.html