封装WebService的APM为Async、Await模式利于asp.net页面调用

Wcf针对Async、Await指令直接可以返回Task<T>结果，但是老旧的系统中还是会有很多是在用Soap的Webservice。直接在Asp.Net页面调用APM方法确实比较麻烦，其实可以直接用TaskFactory封装APM模式为.Net4.5的async await模式，便于页面调用。

下面上实现代码，不多废话，注意注释：

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading;using System.Threading.Tasks;using System.Web;using System.Web.Services.PRotocols;using System.Web.UI;using System.Web.UI.WebControls;namespace Webapplication1{    public partial class _Default : Page    {        protected async void Page_Load(object sender, EventArgs e)        {            //这里不直接用AsyncWebService而用父类SoapHttpClientProtocol的原因是:以后可以针对不同的webservice复用            SoapHttpClientProtocol soapHttpClient = new global::AsyncWebService("http://localhost:3115/AsyncWebService.asmx");            //反射创建APM方法异步委托            var beginFunc = soapHttpClient.GetType()                .GetMethod("BeginHelloWorld")                .CreateDelegate(typeof(Func<string, System.AsyncCallback, object, IAsyncResult>), soapHttpClient) as Func<string, System.AsyncCallback, object, IAsyncResult>;            var endFunc = soapHttpClient.GetType()                .GetMethod("EndHelloWorld")                .CreateDelegate(typeof(Func<IAsyncResult, string>), soapHttpClient) as Func<IAsyncResult, string>;            //打印一下调用异步前线程ID            StringBuilder sb = new StringBuilder();            sb.Append("<br />");            sb.Append("Befort Thread Id:" + Thread.CurrentThread.ManagedThreadId);            sb.Append("<br />");            //用TaskFactory封装APM模式为.Net4.5的async await模式            string result = await Task<string>.Factory.FromAsync<string>(beginFunc,                endFunc, "zhang san", null);            //打印一下调用异步后线程ID            sb.Append("After Thread Id:" + Thread.CurrentThread.ManagedThreadId);            sb.Append("<br />");            sb.Append(result);            ltlResult.Text = sb.ToString();        }    }}

注意需要在Aspx前台启用Async="true"特性。

看一下最终的效果：

前台随便敲了点样式：

<div style="padding: 0;background-color: black;color: white;height:100%;width: 100%;margin: 0 auto;font-size:xx-large;"> <h6>Test Async</h6> <p style="color: yellow;"> <asp:Literal ID="ltlResult" runat="server"></asp:Literal> </p> </div>

本文代码：http://files.cnblogs.com/files/12taotie21/WebApplication1.rar