ASP.NET Mvc Dropdownlist?
===

script

    $(document).ready(function () {
        $("#musteri_sno").change(function () {
            var strSayacID = "";
            strSayacID = $(this)[0].value; // get the selected state id

            var url = "/SayacOkumalari/MusteriSayaclariniGetir/" + strSayacID ;
            // call controller's action
            $.getJSON(url, null, function (data) {
                // do something once the data is retrieved
                $("#sayac_no").empty();
                $.each(data, function (index, optionData) {
                    $("#sayac_no").append("<option value='"
                     + optionData.sno
                     + "'>" + optionData.sayac_seri_no
                     + "</option>");
                });
            });
        })
    .change(); // making sure the event runs on initialization for default value
    });

html 

    <td>
        @Html.DropDownList("musteri_sno", (SelectList)ViewBag.musteri_id, "--Müşteri Seçiniz--", new { id = "musteri_sno" })
    </td>
    <td>
        @Html.DropDownList("sayac_no", Enumerable.Empty<SelectListItem>(), "-- Sayaç Seçiniz --", new { id = "sayac_no" })
    </td>

action

    [HttpGet]
    public ActionResult MusteriSayaclariniGetir(int musteri_sno)
    {
        var sites = entity.TblSayaclar.Where(x => x.musteri_id == musteri_sno).Select(x => new { sno = x.sno, sayac_seri_no = x.seri_no });
        return Json(sites, JsonRequestBehavior.AllowGet);
    }

When I removed parameter musteri_no from `MusteriSayaclariniGetir(int musteri_sno)` action, my codes work correctly.  Is there a problem with url `var url = "/SayacOkumalari/MusteriSayaclariniGetir/" + strStateID;` or different error?

Thanks.