当使用 ajax jQuery 验证注解调用 api 不起作用时？

问：

我在 ASP.NET Core MVC应用程序上工作，我使用ajax jQuery调用API，以防止在单击提交按钮后更改URL。

从

Resignation/RequesterIndex?filenumber=103085

自

Resignation/RequesterIndex

并在不更改 URL 的情况下调用 ajax jQuery 工作成功，但同时验证注解模型状态不起作用。

如何显示验证？

public class ResignationRequester
{
    [Required]
    [Display(Name = "Dept./ Branch: ")]
    public string Dept { get; set; }

    [Required]
    [Display(Name = "Designation: ")]
    public string Designation { get; set; }
}

控制器动作方法：

public class ResignationController : Controller
{
        public ActionResult RequesterIndex(string filenumber)
        {
            return View(resignationRequester);
        }
       
        [HttpPost]
        public ActionResult RequesterIndex(ResignationRequester resignationRequester)
        {
                if (ModelState.IsValid)
                {
                    try
                    {
                        Workforce.InsertToReignation(resignationRequester, (string)Session[SessionKeys.Username], (DateTime)Session[SessionKeys.LastWorkingDate], noticeperiod, (int)Session[SessionKeys.UserCode]);
                    }
                    catch (Exception ex)
                    {
                        ViewBag.errorMsg = "Create Not Done Correctly";
                    }

                    Session[SessionKeys.DirectManager] = GetEmployeeName(Convert.ToString(resignationRequester.DirectManager));
                    Session[SessionKeys.LineManager] = GetEmployeeName(Convert.ToString(resignationRequester.LineManager));

                    if (string.IsNullOrEmpty(ViewBag.errorMsg))
                    {
                        ViewBag.successMessage = "Resignation Submission form Created successfully";
                    }
                }
                else
                {
                    var errors = ModelState.Select(x => x.Value.Errors)
                                            .Where(y => y.Count > 0)
                                            .ToList();
                    ViewBag.errorMsg = "Some Required Fields Not Added";
                    goto InvalidModel;
                }
            }
            else
            {
                ViewBag.errorMsg = "No Data For This File No";
            }

            InvalidModel:

            ViewBag.isPostBack = true;

            return View(resignationRequester);
        }
}

视图ResignationRequester.cshtml

@model HR.WorkforceRequisition.Models.ResignationRequester

@{
    ViewBag.Title = "Requester Index";
}

@using (Html.BeginForm("RequesterIndex", "Resignation", FormMethod.Post, new { enctype = "multipart/form-data", @id = "ResignationApp", style = "padding-top: 50px" }))
{
    @Html.AntiForgeryToken()
    <div class="form-horizontal">
    @if (!string.IsNullOrEmpty(ViewBag.errorMsg))
    {
        <div class="alert alert-danger">
            @ViewBag.errorMsg
        </div>
    }

    @if (!string.IsNullOrEmpty(ViewBag.successMessage))
    {
        <div class="alert alert-success">
            @ViewBag.successMessage
        </div>
    }

    <div class="row">
        <div class="form-group col-md-6 hover">
            <div class="col-md-5">
                @Html.LabelFor(model => model.Dept, htmlAttributes: new { @class = "control-label" })
            </div>

            <div class="col-md-7">
                @Html.EditorFor(model => model.Dept, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Dept, "", new { @class = "text-danger" })
            </div>
        </div>
        <div class="form-group col-md-6 hover">
            <div class="col-md-5">
                @Html.LabelFor(model => model.Designation, htmlAttributes: new { @class = "control-label" })
            </div>

            <div class="col-md-7">
                @Html.EditorFor(model => model.Designation, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Designation, "", new { @class = "text-danger" })
            </div>
        </div>
    </div>

  
    <div class="form-group">
        <div class="col-md-offset-0 col-md-12">
            <input type="submit" value="Submit" class="btn btn-success" />
        </div>
    </div>
</div>
}

@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}

调用 jQuery ajax 将调用操作 Requester Index on Resignation Controller

$("#ResignationApp").submit(function (e) {
                e.preventDefault(); // Prevent the default form submission

                var formData = $(this).serialize();
                console.log("data is" + formData)
                $.ajax({
                    type: "POST",
                    url: '@Url.Action("RequesterIndex", "Resignation")',
                   data: formData,
                    success: function (response) {
                        $("#successMessage").show();
                    },
                    error: function (error) {
                        console.error(error);
                    }
                });
            });

我对此进行了调查，并在ajax jQuery调用中发现了问题

e.preventDefault();

删除它时，验证工作，但同时 URL 会更改

如何使验证工作并且 URL 不更改？

预期结果

当将部门或职务留空时，它必须显示我需要的验证

未更改 URL 时所需的验证错误

但这并没有发生......

如果我从jQuery中删除，它将解决问题验证，但同时URL将从：e.preventdefault

Resignation/RequesterIndex?filenumber=103085 

自

Resignation/RequesterIndex

更新的帖子

if ($("#validateFrom").valid()) {

运行 valid（） 需要哪些 jQuery 脚本 或者你的意思是 validate（）