我的Common.js如下

//处理一般AJAX功能。
function InvokeHander(url,type,data, onSuccess, onFailure) {

    $.ajax({
        url: url, //路径
        type: type, //请求方式
        data: data, //请求的数据
        dataType: "json",
        contentType: "application/json;charset=utf-8",
        beforeSend: function(x) {
            x.setRequestHeader("Content-Type", "application/json;");
        },
        success: function(result) {
            if (onSuccess) {
                if (result.d != undefined)
                    result = result.d;
                onSuccess(result);
            }

        },
        error: function(err) {
            if (onFailure) {
                onFailure(err);
            }
        }

    })

}

aspx页面js如下

 <script type="text/javascript" src="javascript/jquery-1.3.2.min.js"></script>
    <script type="text/javascript" src="javascript/Common.js"></script>
    <script type="text/javascript">
        $(function() {
            $("#d1").change(function() {

                var did = $("#d1").find("option:selected").val();
                if (did != "请选择") {
                    InvokeHander("TypeHandler.ashx","POST","{id:'"+did+"'}" ,
                    function(result) {
                        if (result != null) {
                            for (i = 0; i < result.length; i++) {
                                var item = result[i];
                                alert(item.TypeName);

                            }

                        }
                    },
             function(err) {

                 alert('err');
             });
                }
                else {

                }
            });

        });
   
    </script>

ashx文件如下：

<%@ WebHandler Language="C#" class="TypeHandler" %>

using System;
using System.Web;
using System.Data;
using System.Data.SqlClient;
using System.Collections;
using System.Web.Script.Serialization;
public class TypeHandler : IHttpHandler
{

    public void ProcessRequest(HttpContext context)
    {

        if (context.Request["id"] == null)//这里永久为null用Request.form["id"]也不行
        {
          
        }
        else
        {
            context.Response.Write(GetType(decimal.Parse(context.Request["id"].ToString())));
        }
       
    }

    public bool IsReusable
    {
        get
        {
            return false;
        }

    }

    public string GetType(decimal id)
    {
        ArrayList arr = new ArrayList();
        SqlConnection conn = new SqlConnection("server=PC-200911131211;database=petsdata;uid=sa;pwd=sa123456");
        SqlDataAdapter da = new SqlDataAdapter("select * from infor_type2 where infor_type2_father='" + id + "'", conn);
        DataSet ds = new DataSet();
        da.Fill(ds);
        for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
        {
            arr.Add(new {
                TypeID = ds.Tables[0].Rows[i]["infor_type2_id"].ToString(),
                TypeName=ds.Tables[0].Rows[i]["infor_type2_name"].ToString()
           
            });
       
        }

        JavaScriptSerializer serializer = new JavaScriptSerializer();
        string result = serializer.Serialize(arr);
        return result;
     
    }

   
}
   

假如我把上面请求方法换成POST传进去的data换成: "id="+did ，ashx用request.QueryString["id"]就一点问题都没。

请博客园的高手帮帮我吧。。。。我看见CSDN上也有类似的情况，好像也没解决。

地址：http://topic.csdn.net/u/20091126/17/a015820e-d41f-4689-b6fe-232a098c2699.html