checkbox赋值解决方案

checkbox赋值
<div alt="checkbox赋值解决方案" />

                $.ajax({
                    type: "get",
                    dataType: "json",
                    url: "ReturnCity.ashx",
                    data: {
                        provinceId: $("#s_province").val()
                    },
                    success: function (msg) {
                        $("#s_city").empty();  //清空市区选项
                        $("#s_county").empty();  //清空县区选项

                        //$("<option value='-1'>请选择市/区</option>").appendTo("#s_city");
                        //$("<option value='-1'>请选择位置</option>").appendTo("#s_county"); 
 

                        $.each(msg.returnStr, function (i, n) {
                            //alert(i);
                            $("<option value=" + n.cityID + ">" + n.city + "</option>").appendTo("#s_city");
                        });
                        changeCity();
                    },
                    error: function (msg) {
                        alert(msg);
                    }
                });