ASP. NET中的webservice

在分布式计算中经常要用到WebService，为了更好的学习WebService，写此文供自己记忆。

编译环境:VS2008

在项目中添加一个名称为MyWebService.asmx的Web服务，App_Code文件夹下会新增一个MyWebService.cs文件，编写代码如下:

using System;
using System.Collections;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Xml.Linq;

/// <summary>
///MyWebService 的摘要说明
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
//若要允许使用 ASP.NET AJAX 从脚本中调用此 Web 服务，请取消对下行的注释。
// [System.Web.Script.Services.ScriptService]
public class MyWebService : System.Web.Services.WebService {

    public MyWebService () {

        //如果使用设计的组件，请取消注释以下行
        //InitializeComponent();
    }

    [WebMethod]
    public string HelloWorld() {
        return "Hello World";
    }

}

using System;
using System.Collections;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Xml.Linq;

/// <summary>
///MyWebService 的摘要说明
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
//若要允许使用 ASP.NET AJAX 从脚本中调用此 Web 服务，请取消对下行的注释。 
// [System.Web.Script.Services.ScriptService]
public class MyWebService : System.Web.Services.WebService {

    public MyWebService () {

        //如果使用设计的组件，请取消注释以下行 
        //InitializeComponent(); 
    }

    [WebMethod]
    public string HelloWorld() {
        return "Hello World";
    }
    
}

写好WebService以后，在项目上右键选择“添加Web引用”，可以给WebService起一个命名空间localhost。

添加Web引用成功如下图所示：

下面我们写客户端代码

前端代码:

<form id="form1" runat="server">
    <div>
        <asp:Button ID="Button1" runat="server" Text="同步调用WebService"  />
        <asp:Button ID="Button2" runat="server" Text="异步调用WebService"  />
        <asp:Button ID="Button3" runat="server" Text="另一种异步调用WebService"  />
    </div>
</form>

<form id="form1" runat="server">
    <div>
        <asp:Button ID="Button1" runat="server" Text="同步调用WebService"  />
        <asp:Button ID="Button2" runat="server" Text="异步调用WebService"  />
        <asp:Button ID="Button3" runat="server" Text="另一种异步调用WebService"  />
    </div>
</form>

后台代码:

using System;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
       Button1.Click += new EventHandler(Button1_Click);
       Button2.Click += new EventHandler(Button2_Click);
       Button3.Click += new EventHandler(Button3_Click);
    }


    #region 同步调用

    void Button1_Click(object sender, EventArgs e)
    {
        localhost.MyWebService mws = new localhost.MyWebService();
        string s = mws.HelloWorld();
        Response.Write("<script>alert('"+s+"')</script>");
        //Response.End();
    }

    #endregion


    #region 异步调用

    void Button2_Click(object sender, EventArgs e)
    {
        localhost.MyWebService AsyMWS = new localhost.MyWebService();
        IAsyncResult asyncResult = AsyMWS.BeginHelloWorld(new AsyncCallback(CallbackFunc), "AsyncState");
        string s = AsyMWS.EndHelloWorld(asyncResult);
        Response.Write("<script>alert('" + s + "')</script>");
    }

    void CallbackFunc(IAsyncResult r)
    {
        Response.Write("<script>alert('异步调用完成!')</script>");
    }

    #endregion


    #region 另一种异步调用

    void Button3_Click(object sender, EventArgs e)
    {
        localhost.MyWebService AsyMWS = new localhost.MyWebService();
        AsyMWS.HelloWorldCompleted += new localhost.HelloWorldCompletedEventHandler(AsyMWS_HelloWorldCompleted);
        AsyMWS.HelloWorldAsync();
    }

    void AsyMWS_HelloWorldCompleted(object sender, localhost.HelloWorldCompletedEventArgs e)
    {
        string s = e.Result;
        Response.Write("<script>alert('"+s+"')</script>");
    }

    #endregion
}

using System;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;

public partial class _Default : System.Web.UI.Page 
{
    protected void Page_Load(object sender, EventArgs e)
    {       
       Button1.Click += new EventHandler(Button1_Click);
       Button2.Click += new EventHandler(Button2_Click);
       Button3.Click += new EventHandler(Button3_Click);
    }


    #region 同步调用

    void Button1_Click(object sender, EventArgs e)
    {
        localhost.MyWebService mws = new localhost.MyWebService();
        string s = mws.HelloWorld();
        Response.Write("<script>alert('"+s+"')</script>");
        //Response.End();
    }

    #endregion


    #region 异步调用

    void Button2_Click(object sender, EventArgs e)
    {
        localhost.MyWebService AsyMWS = new localhost.MyWebService();
        IAsyncResult asyncResult = AsyMWS.BeginHelloWorld(new AsyncCallback(CallbackFunc), "AsyncState");
        string s = AsyMWS.EndHelloWorld(asyncResult);
        Response.Write("<script>alert('" + s + "')</script>");
    }

    void CallbackFunc(IAsyncResult r)
    {
        Response.Write("<script>alert('异步调用完成!')</script>");
    }

    #endregion


    #region 另一种异步调用

    void Button3_Click(object sender, EventArgs e)
    {
        localhost.MyWebService AsyMWS = new localhost.MyWebService();
        AsyMWS.HelloWorldCompleted += new localhost.HelloWorldCompletedEventHandler(AsyMWS_HelloWorldCompleted);
        AsyMWS.HelloWorldAsync();
    }

    void AsyMWS_HelloWorldCompleted(object sender, localhost.HelloWorldCompletedEventArgs e)
    {
        string s = e.Result;
        Response.Write("<script>alert('"+s+"')</script>");
    }

    #endregion
}

注:若要使用最后一种异步调用方式需要在前端代码中写入Async="true"，如下图