ASP.NET MVC表单输入不更改列表项的属性值

Question

我正在尝试更改属于Achievement类的属性Rank和Event 。 在我的模型Profile ，有一个Achievement列表。 当视图打开时，我会传递视图模型，并在视图模型构造函数中初始化配置文件模型。 概要文件模型使用模型的构造函数中的5个空对象来初始化成就列表。

但是，当我发布表单时，成就的属性为空/不变， Profile的其他属性确实发生了变化。

视图模型：

    public class EditProfileViewModel
    { 
        public Profile profile { get; set; }

        public EditProfileViewModel()
        {
            profile = new Profile();
        }
    }

模型：

public class Profile
    {
        [Required]
        [StringLength(32, MinimumLength = 3, ErrorMessage = "Your username has to be between 3 and 32 characters long")]
        [RegularExpression(@"^[A-Za-z0-9-_\\s]*$", ErrorMessage = "Your username may only contain alphanumeric characters (a-z, A-Z, 0-9)")]
        public string Username { get; set; }
        public List<Achievement> Achievements;

        [StringLength(1000, ErrorMessage = "Additional text input can not be longer than 1000 characters")]
        [Display (Name = "Additional Information")]
        public string FreeText { get; set; }
        public string SocialURL { get; set; }

        public Profile()
        {
            Achievements = new List<Achievement> { new Achievement(), new Achievement(), new Achievement(), new Achievement(), new Achievement(), };
        }

    public class Achievement
    {
        public int? Rank;
        public Events Event;
    }

控制器：

        [ValidateAntiForgeryToken]
        public IActionResult IndexValidation(EditProfileViewModel edit)
        {
            if (ModelState.IsValid)
            {
                return View("Profile", edit.profile);
            }
            else
            {
                return View("Index", edit);
            }
        }

视图：

<form asp-action="IndexValidation" asp-controller="Profiles" asp-antiforgery="true">
            <div class="form-group">
                <label asp-for="profile.Username" class="control-label"></label>
                <input asp-for="profile.Username" class="form-control" autocomplete="off" />
                <span asp-validation-for="profile.Username" class="text-danger"></span>
            </div>
            <div class="form-group">
                <table>
                    <tr>
                        <td><b>Place</b></td>
                        <td></td>
                        <td><b>Event</b></td>
                    </tr>
                    @for (int i = 0; i < Model.profile.Achievements.Count; i++)
                    {
                        <tr>
                            <td width="135"><input type="number" min="1" asp-for="profile.Achievements[i].Rank" class="form-control" /></td>
                            <td width="20"><span></span></td>
                            <td width="590"><select asp-for="profile.Achievements[i].Event" asp-items="@Html.GetEnumSelectList<Events>()" class="form-control"></select></td>
                        </tr>
                    }
                </table>
            </div>

            <div class="form-group">
                <label asp-for="profile.FreeText" class="control-label"></label>
                <input asp-for="profile.FreeText" class="form-control" autocomplete="off" />
                <span asp-validation-for="profile.FreeText" class="text-danger"></span>
            </div>

            <div class="form-group">
                <label asp-for="profile.SocialURL" class="control-label"></label>
                <input asp-for="profile.SocialURL" class="form-control" autocomplete="off" />
                <span asp-validation-for="profile.SocialURL" class="text-danger"></span>
            </div>

            <div class="form-group">
                <input type="submit" value="Create" class="btn btn-primary" />
            </div>

我在哪里打开视图：

        public IActionResult Profiles()
        {
            EditProfileViewModel vm = new EditProfileViewModel();
            return View("../Profiles/Index", vm);
        }