Uncaught SyntaxError: Unexpected token u in JSON at position 0 when I call $(form).valid()

Question

I have a form like this:

<div class="row">
    @using (Ajax.BeginForm("ImportFromExcel", "QuanLySim", null, new AjaxOptions
                    {
                        UpdateTargetId = "div-form-daily",
                        HttpMethod = "POST",
                        OnBegin = "QuanLyDaiLy.BeforeSend",
                        OnFailure = "QuanLyDaiLy.Error",
                        OnComplete = "QuanLyDaiLy.Success",
                        InsertionMode = InsertionMode.Replace
                    }, new { @class = "form-update", @role = "form", @id = "search-form" }))
    {
        <div class="col-xs-12 col-sm-12 col-md-12">
            <div class="col-xs-12 col-sm-12 col-md-12">
                <div class="form-group">
                    <label for="so-ct" class="col-xs-12 col-sm-12 col-md-2 input-sm">File excel <span class="text-red required">*</span></label>
                    <div class="col-xs-12 col-sm-12 col-md-10 input-sm">
                        @Html.TextBoxFor(model => model.File, new { type = "file", accept = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet, application/vnd.ms-excel", @class = "btn btn-default btn-sm", style = "width: 100%;" })
                    </div>
                    <div class="col-xs-12 col-sm-12 col-md-2"></div>
                    <div class="col-xs-12 col-sm-12 col-md-10 color-red" style="padding-left: 10px; margin-top: 10px">
                        @Html.ValidationMessageFor(model => model.File)
                    </div>
                    <div class="clear"></div>
                </div>
            </div>
            <div class="col-xs-12 col-sm-12 col-md-12">
                <div class="form-group">
                    <label for="so-ct" class="col-xs-12 col-sm-12 col-md-2 input-sm">Giá nhân thêm</label>
                    <div class="col-xs-12 col-sm-12 col-md-10 input-sm">
                        @Html.TextBoxFor(model => model.Rate, new { @class = "form-control input-sm", placeholder = "Nhập tỷ giá cho giá sim..." })
                    </div>
                    <div class="col-xs-12 col-sm-12 col-md-2"></div>
                    <div class="col-xs-12 col-sm-12 col-md-10 color-red" style="padding-left: 10px; margin-top: 10px">
                        @Html.ValidationMessageFor(model => model.Rate)
                    </div>                     

                </div>
            </div>

            <div class="col-xs-12 col-sm-12 col-md-12">
                <div class="form-group">
                    <label for="so-ct" class="col-xs-12 col-sm-12 col-md-2 input-sm">Chọn đại lý <span class="text-red required">*</span></label>
                    <div class="col-xs-12 col-sm-12 col-md-10 input-sm">
                        @Html.DropDownListFor(model => model.AgentId, (IEnumerable<SelectListItem>)ViewBag.Agents, "Chọn...", new { @class = "form-control input-sm add-daily-sim filter-select" })
                    </div>
                    <div class="col-xs-12 col-sm-12 col-md-2"></div>
                    <div class="col-xs-12 col-sm-12 col-md-10 color-red" style="padding-left: 10px; margin-top: 10px">
                        @Html.ValidationMessageFor(model => model.AgentId)
                    </div>
                    <div class="clear"></div>
                </div>
            </div>
            <div class="col-xs-12 col-sm-12 col-md-12">
                <div class="form-group">
                    <label for="so-ct" class="col-xs-12 col-sm-12 col-md-2 ">Đảm bảo đã đúng giá?</label>
                    <div class="col-xs-12 col-sm-12 col-md-1">
                        @Html.CheckBoxFor(model => model.IsSure.HasValue)
                    </div>
                    <label for="so-ct" class="col-xs-12 col-sm-12 col-md-2 ">Xóa sim đại lý</label>
                    <div class="col-xs-12 col-sm-12 col-md-1 ">
                        @Html.CheckBoxFor(model => model.IsXoaSimCu.HasValue)
                    </div>
                </div>
            </div>

            <div class="col-xs-12 col-sm-12 col-md-12 text-center">
                <div class="form-group">
                    <button type="button" class="btn bg-maroon btn-cons btn-sm" id="btn-import-excel">
                        <i class="fa fa-floppy-o fa-lg"></i>&nbsp; Lưu
                    </button>
                    <button class="btn btn-default btn-sm" type="button" onclick="location.href='@Url.Action("Index", "QuanLySim")'"><i class="glyphicon glyphicon-refresh fa-lg"></i>&nbsp; Quay về</button>
                </div>
            </div>
        </div>
    }
</div>

And i call jquery to validate form:

 if (!$(form).valid()) return;

But function form.valid() is error and return message in console like this : VM40309:1 Uncaught SyntaxError: Unexpected token u in JSON at position 0

Everybody can help me the problem?

Thanks all

You are using some Unicode characters in your fields there, try preceding yours strings with 'u' to inform the parser this is expected e.g. `placeholder = u"Nhập tỷ giá cho giá sim..."` — Geek Josh, Sep 03 '16 at 22:56
@Geek Josh : If I remove @Html.CheckBoxFor(model => model.IsSure.HasValue) and @Html.CheckBoxFor(model => model.IsXoaSimCu.HasValue), it have no error. And i think that Unicode characters is not a problem. — Dan LE, Sep 03 '16 at 23:17
You cannot use `CheckBoxFor()` to bind to a `nullable bool` Change `IsSure` to `bool` or use `EditorFor()` (which will generate a dropdownlist with 3 values for `true`, `false` and `null`) — , Sep 03 '16 at 23:56
@Stephen Muecke: i was change datatype from nullable bool to bool but it also error. — Dan LE, Sep 04 '16 at 00:06

score 1 · Answer 1 · answered Apr 04 '18 at 18:39

1

Form validation code is not working properly. please check and also use the unobtrusive ajax as reference on the page : jquery.unobtrusive-ajax.min.js

answered Apr 04 '18 at 18:39

tika

341
2
11

score 0 · Answer 2 · answered Jul 10 '18 at 09:48

I think this is the same problem as https://stackoverflow.com/a/14822755/1808720 Problem lies in combination of jquery 1.9+ and old jquery.validate.unobtrusive.js.

Download latest version of jquery.validate.unobtrusive.js from https://github.com/aspnet/jquery-validation-unobtrusive/releases and it should be fine.

Uncaught SyntaxError: Unexpected token u in JSON at position 0 when I call $(form).valid()

2 Answers2