javascript - 在 asp.net mvc 中提交 Ajax.BeginForm 后 jQuery 代码无法正常工作

Question

我试图将大问题最小化为一个小问题，因此我创建了新的示例 Web 项目； VS 中的 mvc-empty。我在 Home Controller 中创建了一个名为“Index”的 View 。索引查看代码:

@model WebApplication16.ViewModels.Home.IndexVM
@{
    ViewBag.Title = "Index";
}

@Html.Partial("~/Views/Home/_Orders.cshtml", Model.Orders)

@section scripts{
    <script src="~/Scripts/jquery.validate.js"></script>
    <script src="~/Scripts/jquery.validate.unobtrusive.js"></script>
    <script src="~/Scripts/jquery.unobtrusive-ajax.js"></script>
    <script>
        $("#Type").change(function () {



            $('#order-current > img').remove();
            var currentOrder = "#Type_" + $("#Type").find('option:selected').text();

            var $img = $(currentOrder).clone();
            $img.removeClass("hidden");
            $("#order-current").append($img);

            $("#ajax-form").submit();
        });
    </script>
}

家庭 Controller 代码:

public class HomeController : Controller
    {
        [HttpGet]
        public ActionResult Index()
        {
            IndexVM dataVM = new IndexVM();
            GetControlsDataSource(dataVM.Orders);

            return View(dataVM);
        }

        private static void GetControlsDataSource(OrdersVM dataVM)
        {
            List<SelectListItem> typeControlDataSource = new List<SelectListItem>();
            foreach (var en in Enum.GetValues(typeof(TypeEnum)))
            {
                SelectListItem item = new SelectListItem();
                item.Text = en.ToString();
                item.Value = ((int)en).ToString();
                typeControlDataSource.Add(item);
            }
            dataVM.TypeControlDataSource = typeControlDataSource;
        }


        [HttpPost]
        public ActionResult Pay(IndexVM dataVM)
        {
            GetControlsDataSource(dataVM.Orders);
            if (ModelState.IsValid)
            {
                dataVM.Orders.Info = "Info bla bla bla";
                return PartialView("~/Views/Home/_Orders.cshtml", dataVM.Orders);
            }
            else
            {
                return View(dataVM);
            }

        }
    } 

还有一个名为“_Orders”的局部 View ，它被渲染在Index View 上。_Orders局部 View 的代码:

@model WebApplication16.ViewModels.Home.OrdersVM

@using (Ajax.BeginForm("Pay", "Home", new AjaxOptions
{
    InsertionMode = InsertionMode.Replace,
    UpdateTargetId = "result",
}, new { id = "ajax-form" }))
{
    <div id="result">
        <div id="order-current">

        </div>


        <div>
            @Html.TextBoxFor(x => x.Name, new { @class = "form-control", style = "margin-top:10px;", id = "Name" })
            @Html.ValidationMessageFor(x => x.Name)
        </div>

        <div>
            @Html.DropDownListFor(x => x.Type, Model.TypeControlDataSource, new { @class = "form-control", style = "margin-top:10px;", id = "Type", })
            @Html.ValidationMessageFor(x => x.Type)
        </div>
        <div>
            <p>@Model.Info</p>
        </div>
        <button type="submit" class="btn btn-primary" name="ok"> OK</button>
    </div>


}

<div id="orders-container">
    <img id="Type_I" src="~/App_Images/Type_I.png" class="img-responsive hidden" />
    <img id="Type_II" src="~/App_Images/Type_II.png" class="img-responsive hidden" />
    <img id="Type_III" src="~/App_Images/Type_III.png" class="img-responsive hidden"/>
</div>
Index model is described by class IndexVM:
public class IndexVM
    {
        public IndexVM()
        {
            this.Orders = new OrdersVM();
        }

        public OrdersVM Orders { get; set; }
    }

_Orders 模型由类 OrdersVM 描述:

public class OrdersVM
    {

        [Required]
        public string Name { get; set; }

        public string Info { get; set; }

        [Required]
        public TypeEnum Type { get; set; }

        public List<SelectListItem> TypeControlDataSource { get; set; }
    }


public enum TypeEnum
{
    I,
    II,
    III
}

在 DropDownListFor 控件中更改 id=”Type” 的值后，来自隐藏字段的图片应该由位于索引 View 中的 jquery 代码注入(inject)到 id=”order-current” 的容器中，然后操作 ajax-form应该提交。它工作正常，但在调用

return PartialView("~/Views/Home/_Orders.cshtml", dataVM.Orders);

在 HomeController 中，字段 Info 已正确更新，但从“order-current”div 容器注入(inject)的图片消失了。我尝试使用 F12 按钮查看 Google Chrome 中的错误，没有错误，但在“browserLink”脚本中出现了无限循环。我无法解释为什么。我只想在提交 ajax-form 后在 id=”order-current 的容器中看到注入(inject)的图片。如何做到这一点以及我做错了什么？

Answer 1

感谢我的 friend ，我终于解决了这个问题。更新“结果”容器后，jQuery 添加到位于该容器中的控件的所有事件都将取消固定。这就是它崩溃的原因。使其正常工作的方法是创建一个函数并将其固定到 AjaxBeginForm 的事件 OnComplete 上。每次通过 ajax 更新结果容器后，都会调用此函数。我在 Home Controller 中也犯了一个小错误，因为我插入了一个错误的 View 模型类。全部改变后，它看起来像这样；家庭 Controller 代码:

public class HomeController : Controller
    {
        [HttpGet]
        public ActionResult Index()
        {
            IndexVM dataVM = new IndexVM();
            GetControlsDataSource(dataVM.Orders);

            return View(dataVM);
        }

        private static void GetControlsDataSource(OrdersVM dataVM)
        {
            List<SelectListItem> typeControlDataSource = new List<SelectListItem>();
            foreach (var en in Enum.GetValues(typeof(TypeEnum)))
            {
                SelectListItem item = new SelectListItem();
                item.Text = en.ToString();
                item.Value = ((int)en).ToString();
                typeControlDataSource.Add(item);
            }
            dataVM.TypeControlDataSource = typeControlDataSource;
        }


        [HttpPost]
        public ActionResult Pay(OrdersVM dataVM)
        {
            GetControlsDataSource(dataVM);
            if (ModelState.IsValid)
            {
                dataVM.Info = "Info bla bla bla";
                return PartialView("~/Views/Home/_Orders.cshtml", dataVM);
            }
            else
            {
                return View(dataVM);
            }

        }
    }

索引 View :

@model WebApplication16.ViewModels.Home.IndexVM
@{
    ViewBag.Title = "Index";
}

@Html.Partial("~/Views/Home/_Orders.cshtml", Model.Orders)

<div id="orders-container">
    <img id="Type_I" src="~/App_Images/Type_I.png" class="img-responsive hidden" />
    <img id="Type_II" src="~/App_Images/Type_II.png" class="img-responsive hidden" />
    <img id="Type_III" src="~/App_Images/Type_III.png" class="img-responsive hidden" />
</div>

@section scripts{
    <script src="~/Scripts/jquery.validate.js"></script>
    <script src="~/Scripts/jquery.validate.unobtrusive.js"></script>
    <script src="~/Scripts/jquery.unobtrusive-ajax.js"></script>
    <script>

        function imageOnChangeEvent() {
            $("#ajax-form").submit();
        }

        function OnCompleteAjaxForm() {

            $('#order-current > img').remove();
            var currentOrder = "#Type_" + $("#Type").find('option:selected').text();

            var $img = $(currentOrder).clone();
            $img.removeClass("hidden");
            $("#order-current").append($img);
        }

    </script>

}

_Orders 部分 View 代码:

@model WebApplication16.ViewModels.Home.OrdersVM

    <div id="result">
        @using (Ajax.BeginForm("Pay", "Home", new AjaxOptions
        {
            InsertionMode = InsertionMode.Replace,
            UpdateTargetId = "result",
            OnComplete = "OnCompleteAjaxForm()"
        }, new { id = "ajax-form" }))
        {

            <div id="order-current">

            </div>


            <div>
                @Html.TextBoxFor(x => x.Name, new { @class = "form-control", style = "margin-top:10px;", id = "Name" })
                @Html.ValidationMessageFor(x => x.Name)
            </div>

            <div>
                @Html.DropDownListFor(x => x.Type, Model.TypeControlDataSource, new { @class = "form-control", style = "margin-top:10px;", id = "Type", onchange = "imageOnChangeEvent()" })
                @Html.ValidationMessageFor(x => x.Type)
            </div>
            <div>
                <p>@Model.Info</p>
            </div>
            <button type="submit" class="btn btn-primary" id="button_ok" name="ok"> OK</button>


        }
    </div>