本文参考自http://www.cnblogs.com/wangweimutou/p/4409227.html,纯属读书笔记,加深记忆
一、简介
在前面的随笔中,详细的介绍了WCF客户端服务的调用方法,但是那些操作全都是同步的,所以我们需要很长的时间等待服务器的反馈,如何一台服务器的速度很慢,所以客户端得到结果就需要很长的时间,试想一下,如果客户端是个web项目,那么客户体验可想而知,所以为了不影响后续代码执行和用户的体验,就需要使用异步的方式来调用服务。注意这里的异步是完全针对客户端而言的,与WCF服务契约的方法是否异步无关,也就是在不改变操作契约的情况下,我们可以用同步或者异步的方式调用WCF服务。
二、操作示例
1、WCF服务层搭建:新建契约层、服务层、和WCF宿主,添加必须的引用(这里不会的参考本人前面的随笔),配置宿主,生成解决方案,打开Host.exe,开启服务。具体的代码如下:
ICalculate.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.ServiceModel;
using System.Text;
using System.Threading.Tasks;
namespace IService
{
[ServiceContract]
public interface ICalculate
{
[OperationContract]
int Add(int a, int b);
}
}
IUserInfo.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.Text;
using System.Threading.Tasks;
namespace IService
{
[ServiceContract]
public interface IUserInfo
{
[OperationContract]
User[] GetInfo(int? id);
}
[DataContract]
public class User
{
[DataMember]
public int ID { get; set; }
[DataMember]
public string Name { get; set; }
[DataMember]
public int Age { get; set; }
[DataMember]
public string Nationality { get; set; }
}
}
注:必须引入System.Runtime.Serialization命名空间,应为User类在被传输时必须是可序列化的,否则将无法传输
Calculate.cs
using IService;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Service
{
public class Calculate : ICalculate
{
public int Add(int a, int b)
{
return a + b;
}
}
}
UserInfo.cs
using IService;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Service
{
public class UserInfo : IUserInfo
{
public User[] GetInfo(int? id)
{
List<User> Users = new List<User>();
Users.Add(new User { ID = 1, Name = "张三", Age = 11, Nationality = "China" });
Users.Add(new User { ID = 2, Name = "李四", Age = 12, Nationality = "English" });
Users.Add(new User { ID = 3, Name = "王五", Age = 13, Nationality = "American" });
if (id != null)
{
return Users.Where(x => x.ID == id).ToArray();
}
else
{
return Users.ToArray();
}
}
}
}
Program.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Service;
using System.ServiceModel;
namespace Host
{
class Program
{
static void Main(string[] args)
{
using (ServiceHost host = new ServiceHost(typeof(Calculate)))
{
host.Opened += delegate { Console.WriteLine("服务已经启动,按任意键终止!"); };
host.Open();
Console.Read();
}
}
}
}
App.Config
<?xml version="1.0"?>
<configuration>
<system.serviceModel>
<services>
<service name="Service.Calculate" behaviorConfiguration="mexBehavior">
<host>
<baseAddresses>
<add baseAddress="http://localhost:1234/Calculate/"/>
</baseAddresses>
</host>
<endpoint address="" binding="wsHttpBinding" contract="IService.ICalculate" />
<endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"/>
</service>
</services>
<behaviors>
<serviceBehaviors>
<behavior name="mexBehavior">
<serviceMetadata httpGetEnabled="true"/>
<serviceDebug includeExceptionDetailInFaults="true"/>
</behavior>
</serviceBehaviors>
</behaviors>
</system.serviceModel>
</configuration>
ok,打开Host.exe
服务开启成功!
2、新建名为Client的客户端控制台程序,通过添加引用的方式,异步调用WCF服务
添加添加对服务终结点地址http://localhost:6666/UserInfo/的引用,设置服务命名空间为UserInfoServiceNS,点击高级设置,勾选生成异步操作选项,生成客户端代理类和配置文件代码后,完成Client对服务的调用.
ok,开始编写program.cs代码:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Client.UserInfoServiceNS;
namespace Client
{
class Program
{
static void Main(string[] args)
{
UserInfoClient proxy = new UserInfoClient();
proxy.GetInfoCompleted += new EventHandler<GetInfoCompletedEventArgs>(proxy_GetInfoCompleted);//注册proxy_GetInfoCompleted到proxy.GetInfoCompleted中
proxy.GetInfoAsync(null);//开始异步调用
Console.WriteLine("此字符串在调用方法前输出,说明异步调用成功!");
Console.Read();
}
static void proxy_GetInfoCompleted(object sender, GetInfoCompletedEventArgs e)
{
User[] Users = e.Result.ToArray();
Console.WriteLine("{0,-10}{1,-10}{2,-10}{3,-10}", "ID", "Name", "Age", "Nationality");
for (int i = 0; i < Users.Length; i++)
{
Console.WriteLine("{0,-10}{1,-10}{2,-10}{3,-10}",
Users[i].ID.ToString(),
Users[i].Name.ToString(),
Users[i].Age.ToString(),
Users[i].Nationality.ToString());
}
}
}
}
从上面的代码可以看出WCF服务端和WCF客户端采用了事件驱动机制,也就是所谓的发布-订阅模式,不了解的话,请参考本人的C# 委托,当proxy.GetInfoAsync(null)从服务端获取数据成功之后,即开始执行EventHandler<T>上绑定的方法.
public delegate void EventHandler<TEventArgs>(object sender, TEventArgs e);
通过参数类型TEventArgs的Result可以获得返回结果
User[] Users = e.Result.ToArray();
三、通过svcutil生成客户端代理类,并通过重写客户端的服务契约,完成对服务端服务的异步吊用
新建名为Client1的客户端控制台程序,通过svcutil.exe工具生成的客户端代理类,,异步调用WCF服务
(1)、打开cmd,输入cd C:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\Bin
(2)、输入svcutil.exe /out:f:\UserInfoClient.cs /config:f:\App.config http://localhost:6666/UserInfo/ /a /tcv:Version35
ok,生成成功
(5)、将生成的文件拷贝到项目中,引入System.Runtime.Serialization命名空间和System.ServiceModel命名空间
(6)、剩下的步骤和上面的一样