ashx 文件 与js文件数据交互

//js代码

//城市下拉列表

            $("#selPro").change(function() {

                var option = "";

                $.ajax({

                    type: "post",

                    url: "homeHandler/HomeProvince.ashx",

                    dataType: "json",

                    data: "proStr=" + $("#selPro").val(),

                    success: function(message) {

                        if (message != null) {

                            $("#selCity option").remove();

                            option += "<option value=\"0\">==请选择==</option>";

                            $.each(message.city, function(i, item) {

                                option += "<option value=\"" + item.id + "\">" + item.name + "</option>";

                            });

                        }

                        $("#selCity").append(option);

                    }

 

                });

 

            });

 

 

//　　c#代码

public void ProcessRequest(HttpContext context)

    {

 

        //得到城市Id

        int proId = Convert.ToInt32(context.Request.Params["proStr"]);

        if (proId != 0)

        {

            //根据城市Id查询城市下的区县

            List<City> listCity = CityManager.GetAllByProId(proId);

            int i = 0;

 

            StringBuilder strJSON = new StringBuilder();

            strJSON.Append("{\"city\":[");

            foreach (City city in listCity)

            {

                if (i < (listCity.Count - 1))

                {

                    strJSON.Append("{");

                    strJSON.Append("\"id\":");

                    strJSON.Append(Convert.ToInt32(city.CityId));

                    strJSON.Append(",");

                    strJSON.Append("\"name\":\"");

                    strJSON.Append(city.CityName);

                    strJSON.Append("\"},");

                }

                if (i == (listCity.Count - 1))

                {

                    strJSON.Append("{");

                    strJSON.Append("\"id\":");

                    strJSON.Append(Convert.ToInt32(city.CityId));

                    strJSON.Append(",");

                    strJSON.Append("\"name\":\"");

                    strJSON.Append(city.CityName);

                    strJSON.Append("\"}");

                }

                i++;

            }

           

            strJSON.Append("]}");

            context.Response.Write(strJSON.ToString());

 

 

        }

    }