POST 500 (Internal Server Error) ajax,mvc

Question

I have ajax request that sends data to my controller , it collects value of my dropdown

the error is

POST http://localhost:65070/form/create 500 (Internal Server Error) 

response of error is

The required anti-forgery form field "__RequestVerificationToken" is not present.

UPDATE My Form

@using (Html.BeginForm())
{
    @Html.AntiForgeryToken()
    @Html.ValidationSummary(true)

    <fieldset>
        <legend>Form</legend>

        <div class="editor-label">
            @Html.LabelFor(model => model.FormName)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.FormName)
            @Html.ValidationMessageFor(model => model.FormName)
        </div>


        <div class="editor-label">
            @Html.LabelFor(model => model.MasterID, "MasterModule")
        </div>
        <div class="editor-field">
            @Html.DropDownList("MasterID", String.Empty)
            @Html.ValidationMessageFor(model => model.MasterID)
        </div>
        <select id="State" name="state"></select><br />
        <p>
            <input type="submit" value="Create" />
        </p>

    </fieldset>
}

My ajax Request

$('#State').change(function () {
  var a = $('#State').val();
    $.ajax({
                url: "/form/create",
                type: "POST",
                data: { 'SubID': a },
                success: function (result) {
                    //        console.log(result);
                }
            });
        });

My controller

public ActionResult Create(Form form, int SubID)
        {
            if (ModelState.IsValid)
            {
                form.SubId =SubID;
                form.CreatedDate = DateTime.Now;
                form.CreatedBy = 1;
                form.CreatedDate = DateTime.Now;
                form.IsActive = true;
                form.ModifyBy = 1;
                form.ModifyDate = DateTime.Now;

                db.Forms.Add(form);
                db.SaveChanges();
                return RedirectToAction("Index");
            }

            ViewBag.MasterID = new SelectList(db.Departments, "MasterId", "ModuleName", form.MasterID);
            return View(form);
        }

It is giving 500 internal error.. its awkward plz help

Answer 1

I have an example that I have used in my applications. In the controller, you must place

[HttpPost]
[ValidateAntiForgeryToken]
    public JsonResult Verificar(int idempleado, string desde, string hasta)
     {
      ...
     return Json(suiche, JsonRequestBehavior.AllowGet);
     }

In the view, I have an ajax function

    function Verificar(desde, hasta) {
        var token = $('[name=__RequestVerificationToken]').val();
        var empleadoId = parseInt($('#empleadoId').val());
        var url = '/Settlements/Verificar';
        var settings = {
            "async": true,
            "crossDomain": true,
            "url": url,
            "method": "POST",
            "data": { __RequestVerificationToken: token, idempleado: empleadoId, desde: desde, hasta: hasta, }
        }
        $.ajax(settings).done(function (response) {
            if (response) {
                $('#mensajefrom').text(null);
                $('#mensajeto').text(null);
            } else {
                $('#mensajefrom').text("There is another settlement with that date range");
                $('#mensajeto').text("There is another settlement with that date range");
            }
        });
    }

in the form, I use @Html.AntiForgeryToken()

Answer 2

Your post method must have the [ValidateAntiForgeryToken] attribute. Either remove the attribute or in the view, add the token

@Html.AntiForgeryToken()

and pass it back in the ajax function

$('#State').change(function () {
  var a = $('#State').val();
  var token = $('[name=__RequestVerificationToken]').val();
  $.ajax({
    ....
    data: { __RequestVerificationToken: token, 'SubID': a },
    ....

Note the form parameter is not necessary in the action method

[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Create(int SubID)
{
  ....