Question

我有以下问题无法从下拉列表中获取我尝试了几周来解决的值。以下是我正在使用的视图模型

    namespace Training.ViewModels
{
    public class RosterViewModel
    {
        public Guid RosterViewModelId { get; set; }
        public List<ClassAttendance> ClassAttendances { get; set; }
        public TRSClass TRSClass { get; set; }
        public ClassRoster Roster { get; set; }
        public Student Student { get; set; }
        public string AttendanceCodeId { get; set; }
    }    
    public class ClassAttendance
    {
        public List<Guid> ClassRosterId { get; set; }
        public int EnrollmentId {get; set;}
        public string StudentName { get; set; }      
        public List<int> AttendanceCodeId { get; set; }
        public List<DateTime> ClassDate { get; set; }
        public IEnumerable<SelectListItem> AttendnaceCodes { get; set; }
    }
}

使用的视图具有以下代码

    @model Training.ViewModels.RosterViewModel
@using Training.UtilModels
@{
    ViewBag.Title = "Class Attendance";
}
@using (Html.BeginForm())
{ 
    @Html.HiddenFor(model => model.RosterViewModelId)
    <table id="Events" class="table table-striped">
        <thead>
            <tr>
                <th></th>
                <th>Student</th>
                @for (int i = 1; i <= Model.TRSClass.Course.NoDays; i++)
                {
                    <th>@BusinessDay.AddWorkDays(Model.TRSClass.ClassStartDate, i).AddDays(-1).ToShortDateString()</th>
                }
            </tr>
        </thead>
        <tbody>
          @* @foreach (var x in Model.ClassAttendances)*@ 
            @for (int i = 0; i < Model.ClassAttendances.Count; i++ )
            {
                <tr>
                    <td>                        
                        @Html.HiddenFor(modelItem => modelItem.ClassAttendances[i].EnrollmentId)
                    </td>    
                    <td>@Html.DisplayFor(modelItem => modelItem.ClassAttendances[i].StudentName)</td>
                    @for (int y = 0; y < Model.TRSClass.Course.NoDays; y++)
                    {
                        <td>
                            @Html.HiddenFor(modelItem => modelItem.ClassAttendances[i].ClassRosterId[y])
                            @Html.HiddenFor(modelItem => modelItem.ClassAttendances[i].AttendanceCodeId[y], new { @id = "codeId" })
                            @Html.HiddenFor(modelItem => modelItem.ClassAttendances[i].ClassDate[y])                           
                            @Html.DropDownList("AttendanceCodeId", ViewBag.AttendanceCodeId as SelectList, Model.ClassAttendances[i].AttendanceCodeId[y] != 0 ? Model.ClassAttendances[i].AttendnaceCodes.Where(t => t.Value == Model.ClassAttendances[i].AttendanceCodeId[y].ToString()).Select(t => t.Text).FirstOrDefault() : "Select", new { @id = "codelist" })
                        </td>
                    }
                </tr>
            }
        </tbody>
    </table>        
    <div class="form-group">
        <div class="col-md-offset-2 col-md-10">
            @if (Model.TRSClass.ClassEndDate >= DateTime.Today)
            {
                <div class="btn btn-default">
                    <input type="submit" value="Save" class="btn btn-default" />
                </div>
            }
            <div class="btn btn-default">
                @Html.ActionLink("Class List", "Index", "Classes")
            </div>
        </div>
    </div>
}    
@section scripts {
    @Scripts.Render("~/bundles/jqueryval")        
    <script type="text/javascript">
        $(document).ready(function () {
            $('#codelist').change(function () {
                var res = $(this).val();
                $('#codeId').val(res);
            });
        });
    </script>
}

和控制器编辑功能如下：

// GET: Class Roster
public ActionResult Edit(Guid? id)
{
    if (id == null)
    {
        return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
    }
    RosterViewModel model = new RosterViewModel();
    model.RosterViewModelId = (Guid)id;
    model.ClassAttendances = new List<ClassAttendance>();
    var roster = db.ClassRoster.Where(c => c.TRSClass.TRSClassId == id)
                  .Include(c => c.TRSClass)
                  .Include(c => c.Enrollments)
                  .OrderBy(c => c.EnrollmentId).ThenBy(c => c.ClassDate)
                  .ToList();
    model.TRSClass = roster.Select(c => c.TRSClass).FirstOrDefault();

    ViewBag.AttendanceCodeId = db.AttendanceCodes.Select(m => new SelectListItem { Text = m.AttendanceCd, Value = m.AttendanceCodeId.ToString() });


    ClassAttendance a = new ClassAttendance();
    a.ClassRosterId = new List<Guid>();
    a.AttendanceCodeId = new List<int>();
    a.ClassDate = new List<DateTime>();
    a.AttendnaceCodes = db.AttendanceCodes.Select(m => new SelectListItem { Text = m.AttendanceCd, Value = m.AttendanceCodeId.ToString() });
    string studentName = model.TRSClass.Enrollments.OrderBy(e => e.EnrollmentId).Select(e => e.Student.FullName).FirstOrDefault();
    int i = 1;
    foreach (ClassRoster c in roster)
    {
        if (!studentName.Equals(c.TRSClass.Enrollments.Where(t => t.EnrollmentId == c.EnrollmentId).Select(t => t.Student.FullName).FirstOrDefault()))
        {                       
            model.ClassAttendances.Add(a);
            a = new ClassAttendance();
            a.ClassRosterId = new List<Guid>();
            a.AttendanceCodeId = new List<int>();
            a.ClassDate = new List<DateTime>();
            a.AttendnaceCodes = db.AttendanceCodes.Select(m => new SelectListItem { Text = m.AttendanceCd, Value = m.AttendanceCodeId.ToString() });
            studentName = c.TRSClass.Enrollments.Where(t => t.EnrollmentId == c.EnrollmentId).Select(t => t.Student.FullName).FirstOrDefault();
            i = 1;
        }
        a.ClassRosterId.Add((Guid)c.ClassRosterId);
        a.EnrollmentId = c.EnrollmentId;
        a.StudentName = c.TRSClass.Enrollments.Where(t => t.EnrollmentId == c.EnrollmentId).Select(t => t.Student.FullName).FirstOrDefault();
        a.AttendanceCodeId.Add(c.AttendanceCodeId);
        a.ClassDate.Add(BusinessDay.AddWorkDays(model.TRSClass.ClassStartDate, i).AddDays(-1));
        i++;
    }
    model.ClassAttendances.Add(a);
    return View(model);
}

[HttpPost]
public ActionResult Edit(RosterViewModel model)
{
    if (ModelState.IsValid)
    {
        TRSClass theClass = db.Classes.Find(model.RosterViewModelId);
        //db.Entry(model).State = EntityState.Modified;

        foreach (ClassAttendance c in model.ClassAttendances) 
        {
            for (int i = 0; i < theClass.Course.NoDays; i++)
            {
                ClassRoster CR = db.ClassRoster.Find(c.ClassRosterId[i]);
                CR.AttendanceCodeId = c.AttendanceCodeId[i];
            }
        }    
        db.SaveChanges();
        return RedirectToAction("Index", new { id = theClass.TRSClassId });
    }
    else
    {
        return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
    }
}

我似乎无法从下拉列表中获取值或获取jquery函数来更新隐藏字段。任何见解都将受到赞赏。

Answer 1

在我看来，我更改了循环以包含下拉列表的索引和下面的相关字段代码

@{
        int z = 0;
        for (int i = 0; i < Model.ClassAttendances.Count; i++ )
        {
            <tr>
                <td>                        
                    @Html.HiddenFor(modelItem => modelItem.ClassAttendances[i].EnrollmentId)
                </td>

                <td>@Html.DisplayFor(modelItem => modelItem.ClassAttendances[i].StudentName)</td>
                @for (int y = 0; y < Model.TRSClass.Course.NoDays; y++)
                {        
                    <td>
                        @Html.HiddenFor(modelItem => modelItem.ClassAttendances[i].ClassRosterId[y])
                        @Html.HiddenFor(modelItem => modelItem.ClassAttendances[i].AttendanceCodeId[y], new { @id = "codeId" + @z })
                        @Html.HiddenFor(modelItem => modelItem.ClassAttendances[i].ClassDate[y])                           
                        @Html.DropDownList("AttendanceCodeId", ViewBag.AttendanceCodeId as SelectList, Model.ClassAttendances[i].AttendanceCodeId[y] != 0 ? Model.ClassAttendances[i].AttendnaceCodes.Where(t => t.Value == Model.ClassAttendances[i].AttendanceCodeId[y].ToString()).Select(t => t.Text).FirstOrDefault() : "Select", new { @id = "codelist" + @z, @class = "form-control" })
                    </td>
                    z++;
                }
            </tr>
        }
      }

然后我修改了我的JQuery脚本以循环操作并使用新值更新模型，然后将其发布到控制器以进行数据库更新

<script type="text/javascript">
    $(document).ready(function () {
        $('.form-control').each(function(i){
            $('#codelist' + i).change(function () {
                var res = $(this).val();
                $('#codeId' + i).val(res);
            });
        });         
    });
</script>

MVC 5使用下拉列表更新多个记录

1 个答案: