使用jQuery调用ASP.NET WebService的简易教程

鉴于使用Javascript调用Web Service配置略麻烦，所以记录一下。

1. 新建一个Web服务（WebService.asmx）

2. 取消注释
// [System.Web.Script.Services.ScriptService]

3. 在public string HelloWorld()方法前加上
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
并且需要
using System.Web.Script.Services;

4. 在web.config中加入

<system.web>
   <webServices>
     <protocols>
       <add name="HttpSoap" />
       <add name="HttpPost" />
       <add name="HttpGet" />
       <add name="Documentation" />
     </protocols>
   </webServices>
</system.web>

完整代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.IO;
using System.Web.Script.Services;

namespace WebService
{
    /// <summary>
    /// WebService 的摘要说明
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    [System.ComponentModel.ToolboxItem(false)]
    // 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 WebService : System.Web.Services.WebService
    {
        [WebMethod]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public string HelloWorld()
        {
            try
            {
                return "Hello World";
            }
            catch (Exception e)
            {
                File.WriteAllText(e.Message + "\r\n" + e.StackTrace, "log.txt");
                throw;
            }
        }
 }
}

客户端调用代码：

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
  <meta name="generator" content="HTML Tidy for HTML5 (experimental) for Windows https://github.com/w3c/tidy-html5/tree/c63cc39" />
  <title>AJAX</title>
  <script src="jquery-2.0.3.min.js" type="text/javascript">
</script>
  <script>
function ajax() {
    $.ajax({
        type: "post",
        contentType: "application/json",
        url: "http://localhost/webservice.asmx/HelloWorld",
        success: function(msg) {
            alert(JSON.stringify(msg));
        }
    });
}
  </script>
</head>
<body>
  <form>
    <input id="btn" type="button" onclick="ajax()" value="click" />
  </form>
</body>
</html>