Jquery ajax url在下拉列表更改时未被调用？

我试图在下拉菜单更改函数上调用jQueryAjax，但在更改下拉菜单时似乎什么也没发生。代码写在下面

 $(document).ready(function () {
         $("#locationList").change(function () {
             FillCashSafe();
         })

     });
 function FillCashSafe() {
         var locationNo = document.getElementById('<%=locationList.ClientID%>').value;             
         alert(locationNo);//**alert is working properly**
         $.ajax({                 
             type: "POST",               
             contentType: "application/json; charset=utf-8",
             url: '<%=ResolveUrl("~/HealthReport.aspx/GetCashsafes") %>',
             data: "{}",
             dataType: "json",
             success: function (data) {
                 $.each(data.d, function (key, value) {                        
                     $("#CashSafeList").append($("<option></option>").val(value.CashsafeId).html(value.CashsafeDisplaySerialNo));
                 });
             },
             error: function (result) {
                 $("#CashSafeList").append($("<option></option>").val("-1").html("Select one"));
             }
         });
     }

 [WebMethod]
    public static Cashsafe[] GetCashsafes(string Location)
    {
        Decimal userId = (Decimal)AMSECSessionData.userId;
        List<Cashsafe> cashsafes = DropDown.getCashSafeListLocationwise(userId, Convert.ToInt32(Location));
        return cashsafes.ToArray();
    }

代码隐藏写在下面

 $(document).ready(function () {
         $("#locationList").change(function () {
             FillCashSafe();
         })

     });
 function FillCashSafe() {
         var locationNo = document.getElementById('<%=locationList.ClientID%>').value;             
         alert(locationNo);//**alert is working properly**
         $.ajax({                 
             type: "POST",               
             contentType: "application/json; charset=utf-8",
             url: '<%=ResolveUrl("~/HealthReport.aspx/GetCashsafes") %>',
             data: "{}",
             dataType: "json",
             success: function (data) {
                 $.each(data.d, function (key, value) {                        
                     $("#CashSafeList").append($("<option></option>").val(value.CashsafeId).html(value.CashsafeDisplaySerialNo));
                 });
             },
             error: function (result) {
                 $("#CashSafeList").append($("<option></option>").val("-1").html("Select one"));
             }
         });
     }

 [WebMethod]
    public static Cashsafe[] GetCashsafes(string Location)
    {
        Decimal userId = (Decimal)AMSECSessionData.userId;
        List<Cashsafe> cashsafes = DropDown.getCashSafeListLocationwise(userId, Convert.ToInt32(Location));
        return cashsafes.ToArray();
    }

标记如下

<div class="controls">
   <select class="chzn-select" data-rel="chosen" id="locationList" name="Location"  runat="server">
   </select>
</div>

---

将httppost属性放在服务器方法上，然后重试

[WebMethod]
[HttpPost]
    public static Cashsafe[] GetCashsafes(string Location)
    {
        Decimal userId = (Decimal)AMSECSessionData.userId;
        List<Cashsafe> cashsafes = DropDown.getCashSafeListLocationwise(userId, Convert.ToInt32(Location));
        return cashsafes.ToArray();
    }

和aloso通道位置，如下所示

$.ajax({                 
             type: "POST",               
             contentType: "application/json; charset=utf-8",
             url: '<%=ResolveUrl("~/HealthReport.aspx/GetCashsafes") %>',
             data: "{'Location' : locationNo}",
             dataType: "json",
             success: function (data) {
                 $.each(data.d, function (key, value) {                        
                     $("#CashSafeList").append($("<option></option>").val(value.CashsafeId).html(value.CashsafeDisplaySerialNo));
                 });
             },
             error: function (result) {
                 $("#CashSafeList").append($("<option></option>").val("-1").html("Select one"));
             }
         });

---

是否调用了WebMethod？我的意思是是否调用了codebehind中的GetCashsafes方法？是的。如上所示，您是否收到任何错误消息或您的下拉列表中填写了Select One是的，我在error函数中添加了alertError，警报显示。我按照您的建议进行了尝试，但似乎什么也没有发生