javascript - jQuery:与 removeData() 在不适当的时间执行冲突

Question

我有一个模态窗口用于更新或添加新对象 Store。

此模式被远程调用，其信息是从 ASP.NET 中构造的 GET 方法加载的。

调用模态的按钮:

<div class="btn-group" id="modalbutton">
    <a id="createEditStoreModal" data-toggle="modal" asp-action="Create" 
         data-target="#modal-action-store" class="btn btn-primary">
            <i class="glyphicon glyphicon-plus"></i>  NEW STORE
        </a>
</div>

模态的 Html:

@model Application.Models.ApplicationviewModels.StoreIndexData
@using Application.Models

<form asp-action="Create" role="form">    
        @await Html.PartialAsync("_ModalHeader", new ModalHeader
    { Heading = String.Format("Actualización de Modelo: Tiendas") })

        <div asp-validation-summary="ModelOnly" class="text-danger"></div>
        <div class="modal-body form-horizontal">
            <div class="form-group">
                <label asp-for="DepartmentID" class="col-md-2 control-label"></label>
                <div class="col-md-10">
                    <select asp-for="DepartmentID" class="form-control"
                            asp-items="@(new SelectList(@ViewBag.ListofDepartment,"DepartmentID","DepartmentName"))"></select>
                </div>
            </div>
            <div class="form-group">
                <label class="col-md-2 control-label">Distrito</label>
                <div class="col-md-10">
                    <select class="form-control" id="DistrictID" name="DistrictID" asp-for="DistrictID"
                            asp-items="@(new SelectList(@ViewBag.ListofDistrict,"DistrictID","DistrictName"))"></select>
                </div>
            </div>
            {... more elements}
       </div>
</form>

获取方法:

    public IActionResult Create(int? id)
    {
        List<Department> DepartmentList = new List<Department>();
        DepartmentList = (from department in _context.Departments
                          select department).ToList();
        DepartmentList.Insert(0, new Department { DepartmentID = 0, DepartmentName = "-- Seleccione Departamento --" });
        ViewBag.ListofDepartment = DepartmentList;

        StoreIndexData edit = new StoreIndexData();
        List<District> ListofDistrict = new List<District>();
        ListofDistrict.Insert(0, new District { DistrictID = 0, DistrictName = "-- PRUEBA --" });
        ViewBag.ListofDistrict = ListofDistrict;

        return PartialView("~/Views/Shared/Stores/_Create.cshtml");
    }

问题:

我有以下 jQuery，它会在模态打开后为 DistrictID 赋值:

<script type="text/javascript">

    var wasclicked = 0;
    var $this = this;

    $(document).ready(function () {

        document.getElementById("modalbutton").onclick = function () {
            //is AddNew Store button is hitted, this var = 1
            wasclicked = 1;
        };

        $('#modal-action-store').on('hidden.bs.modal', function () {
            //global.wasclicked = 0;
            wasclicked = 0;
            $(this).removeData('bs.modal');
        });

        $('#modal-action-store').on('shown.bs.modal', function (e) {
            console.log($('#DistrictID').length);
            //if wasclicked equals 1 that means we are in the AddNew Store scenario.
            if (wasclicked == 1) {
                //a default value is sent to District dropdownlist
                var items = "<option value='0'>-- Seleccione Distrito --</option>";
                $('#DistrictID').html(items);
            };
        });
    });
</script>

现在的问题是，在执行这一行 jQuery 之后，分配给 DistrictID 的值被覆盖:

  ViewBag.ListofDistrict = ListofDistrict; //"-- PRUEBA --"

这一行丢失了:

var items = "<option value='0'>-- Seleccione Distrito --</option>";

我怀疑来自 Controller 的信息覆盖了模态中来自 jQuery 的任何结果。

调试后我确定了三个不同的时刻:

时刻 1:我们第一次打开模式

• 模态还没有打开，jQuery 执行
• 因此，它不识别 DistrictID
• GET 操作的结果填充模态的输入。

时刻 2 - 第 1 部分:我们第二次打开模态

• 这次模式在 jQuery 执行之前打开
• 在我们从 jQuery 分配值之前，DistrictID 具有来自 GET 方法的值

时刻 2 - 第 2 部分:分配来自 jQuery 的值时

• 来自 jQuery 的值分配给 DistrictID
• 该值将被 GET 操作的结果覆盖

问题:

任何人都可以解释或帮助我理解可能导致这种情况的原因吗？我还能做些什么来确定这背后的原因？

Answer 1

尝试将分配给 districtID 的 html 从您的主视图移动到模态弹出 View 的 document.ready。

    @model Application.Models.ApplicationviewModels.StoreIndexData
    @using Application.Models

    <form asp-action="Create" role="form">    
            @await Html.PartialAsync("_ModalHeader", new ModalHeader
        { Heading = String.Format("Actualización de Modelo: Tiendas") })

            <div asp-validation-summary="ModelOnly" class="text-danger"></div>
            <div class="modal-body form-horizontal">
                <div class="form-group">
                    <label asp-for="DepartmentID" class="col-md-2 control-label"></label>
                    <div class="col-md-10">
                        <select asp-for="DepartmentID" class="form-control"
                                asp-items="@(new SelectList(@ViewBag.ListofDepartment,"DepartmentID","DepartmentName"))"></select>
                    </div>
                </div>
                <div class="form-group">
                    <label class="col-md-2 control-label">Distrito</label>
                    <div class="col-md-10">
                        <select class="form-control" id="DistrictID" name="DistrictID" asp-for="DistrictID"
                                asp-items="@(new SelectList(@ViewBag.ListofDistrict,"DistrictID","DistrictName"))"></select>
                    </div>
                </div>
                {... more elements}
           </div>
    </form>

<script type="text/javascript">

    $(document).ready(function () {
            //if wasclicked equals 1 that means we are in the AddNew Store scenario.
            if (wasclicked == 1) {
                //a default value is sent to District dropdownlist
                var items = "<option value='0'>-- Seleccione Distrito --</option>";
                $('#DistrictID').html(items);
            }
    });

</script>

PS:也可以使用默认选项。引用下面的代码。

<div class="form-group">
 <label class="col-md-2 control-label">Distrito</label>
  <div class="col-md-10">
   <select class="form-control" id="DistrictID" name="DistrictID" asp-for="DistrictID" asp-items="@(new SelectList(@ViewBag.ListofDistrict,"DistrictID","DistrictName"))">
     <option value='0'>-- Seleccione Distrito --</option>
  </select>
 </div>
</div>