关于C#中ajax跨域访问问题

<script type="text/javascript">
  function ajaxsubmit(name,phone) {
   $.ajax({
    type: "get",
    url: "http://10.10.10.132:35709/AppInterface/ResourceInsert.ashx",
    data: { "share_name": encodeURI(name), "telphone": encodeURI(phone), "fromtype": 4 },
    dataType : "jsonp",
    jsonp: "callback",
    jsonpCallback: "successcallback",
    success: function (json) {
     alert(json.msg);
    },
    error:function(e){
     alert("提交失败！请稍后再试");
    }
   });
  }
 </script>

public class ResourceInsert : IHttpHandler
 {
  public void ProcessRequest(HttpContext context)
  {
   context.Response.ContentType = "application/json";
   context.Response.ContentEncoding = System.Text.Encoding.UTF8;
   cms.Model.Resource model = new Model.Resource();
   cms.BLL.Resource bll = new BLL.Resource();
   //你所需要进行的操作
   model.share_name = HttpUtility.UrlDecode(context.Request["share_name"]);
   model.ask_telphone = HttpUtility.UrlDecode(context.Request["telphone"]);
   model.back_row_one = context.Request["fromtype"];
   ConvertHelper ch = new ConvertHelper();
   model.share_name = ch.RemoveSpecialChar(model.share_name);
   //successcallback为跨域请求回调函数，切记必不可少。获取方式也可以为context.Request["callback"]，
   //对应前端页面发起请求的jsonp和jsonpCallback格式为:jsonp_value=jsonpCallback_value
   if (bll.Exists(model.share_name, model.ask_telphone))
   {
    Message temp = new Message(1, "我们已收到您的请求额！请勿重复提交！", null);
    context.Response.Write("successcallback" + "(" + JsonConvert.SerializeObject(temp) + ")");
    context.Response.End();
    return;
   }
   else
   {
    if (bll.Add(model) > 0)
    {
     Message temp = new Message(1, "提交成功，我们工作人员会尽快回复你！感谢关注！", null);
     context.Response.Write("successcallback" + "(" + JsonConvert.SerializeObject(temp) + ")");
     context.Response.End();
     return;
    }
    else
    {
     Message temp = new Message(0, "请确认信息填写无误！", null);
     context.Response.Write("successcallback" + "(" + JsonConvert.SerializeObject(temp) + ")");
     context.Response.End();
     return;
    }
   }
  }
  public bool IsReusable
  {
   get
   {
    return false;
   }
  }
 }

<system.webServer>
 <httpProtocol>
  <customHeaders>
  <add name="Access-Control-Allow-Methods" value="OPTIONS,POST,GET"/>
  <add name="Access-Control-Allow-Headers" value="x-requested-with,content-type"/>
  <add name="Access-Control-Allow-Origin" value="*" />
  </customHeaders>
 </httpProtocol>
 </system.webServer>