搞来有搞去终于有了个结果，主要是一开始犯了一些低级错误。

对于json不太了解的童鞋，可以看看这个：http://www.dreamdu.com/blog/2008/10/19/json_in_javascript/

这个例子中主要是从数据库中读取数据，转换成JSON格式，传递给前端，废话少说上代码：

protected void Page_Load(object sender, EventArgs e){string b = Request["callback"];string name = Context.Request["name"];//数据库操作SqlConnection thisConnection = new SqlConnection("Data Source=localhost;Initial Catalog=commodities; uid=sa;Password=123");string command = "select * from InterestStore where UserID = " + name;SqlDataAdapter thisAdapter = new SqlDataAdapter(command, thisConnection);SqlCommandBuilder thisCommandBuilder = new SqlCommandBuilder(thisAdapter);DataSet thisDataSet = new DataSet();thisAdapter.Fill(thisDataSet, "IStore");//将数据表转换成JSON数据string ss = GetJson(thisDataSet, "IStore");//返回到前端Response.Write(ss);Response.End();//Response.End把前面的内容都输出了，阻止了后面html相关内容的输出}

下面是将数据转化成JSON代码（改了好长时间，哈哈）

/// <summary>/// 获取Json数据/// </summary>/// <param name="dSet">数据集</param>/// <param name="strTableName">表名</param>/// <returns></returns>private string GetJson(DataSet dSet, string strTableName){StringBuilder sBuilder = new StringBuilder();sBuilder.Append("{");//sBuilder.Append(" " + strTableName + ":{");sBuilder.Append("\"" + strTableName +"\":[");try {for (int i = 0; i < dSet.Tables[strTableName].Rows.Count; i++){sBuilder.Append("{");for (int j = 0; j < dSet.Tables[strTableName].Columns.Count; j++){sBuilder.AppendFormat("\"{0}\":\"{1}\",", dSet.Tables[strTableName].Columns[j].ColumnName, dSet.Tables[strTableName].Rows[i][j].ToString());}sBuilder.Remove(sBuilder.ToString().LastIndexOf(','), 1);sBuilder.Append("},");}sBuilder.Remove(sBuilder.ToString().LastIndexOf(','), 1);sBuilder.Append("]");sBuilder.Append("}");//sBuilder.Append(" };");return sBuilder.ToString();}catch (Exception es){throw new Exception(es.Message);}}

前台返回的数据：

{"IStore":[{"SOIID":"1 ","UserID":"001 ","StoreID":"47 ","Attention":"10"},{"SOIID":"2 ","UserID":"001 ","StoreID":"77 ","Attention":"8"},{"SOIID":"3 ","UserID":"001 ","StoreID":"81 ","Attention":"8"},{"SOIID":"4 ","UserID":"001 ","StoreID":"42 ","Attention":"7"},{"SOIID":"5 ","UserID":"001 ","StoreID":"81 ","Attention":"6"},{"SOIID":"6 ","UserID":"001 ","StoreID":"114 ","Attention":"6"},{"SOIID":"7 ","UserID":"001 ","StoreID":"106 ","Attention":"8"},{"SOIID":"8 ","UserID":"001 ","StoreID":"116 ","Attention":"6"}]}

前台执行ajax调用的代码

xhr.get({//请求页面url: "WebForm3.aspx",//参数content: { name: sname },//数据格式handleAs: "json",//当执行成功时调用的方法load: function (newContent) {try {var str = newContent;console.log(str);console.log("ddddddddddddddddddd");console.log(dojo.toJson(str));}catch (err){ console.log(err); }//dom.byId("txtSuggestion").value = people.programmers[0].lastName;dom.byId("txtSuggestion").value = newContent.IStore[2].StoreID;},//失败时调用的方法error: function (err) {//alert("error");alert(err);}});