从forloop [i]

Question

我试图获取所选复选框的值并将其传递给我的操作，以便我可以更改角色。我有一个模型属性的复选框，并用for循环填充。我有一个Beginform可以解决这个问题，但是我的提交不在forloop中，所以我无法将选中的复选框用于操作。 问题是我曾经使用相同的代码来工作，所以我知道它可以工作。当我的视图上只有1 beginForm（）时，就可以使用它。我将选定的复选框用户发送给我的操作，它成功更改了角色。现在，我很难将用户发送到操作上。 这是我的代码

// View
                @using (Html.BeginForm("AssignAdmin", "SuperAdmin", FormMethod.Post))
                {
                    @Html.AntiForgeryToken()
                    <div class="panel-body">
                        <div class="clearfix"></div>
                        @for (var i = 0; i < Model.lstUsers.Count(); i++)
                        {
                            <div class="col-md-4">
                                <div>
                                    @Html.CheckBoxFor(u => Model.lstUsers[i].SelectedUsers)
                                    <label>
                                        @Html.DisplayFor(u => Model.lstUsers[i].Username)
                                        @Html.HiddenFor(u => Model.lstUsers[i].UserId)
                                        @Html.HiddenFor(u => Model.lstUsers[i].Name)
                                    </label>
                                </div>
                            </div>
                        }
                    </div>
                    <div class="panel-footer form-group">
                        <input type="submit" value="Assign Role" class="btn btn-success" />

                        @Html.ActionLink("Cancel", "Dashboard", "SuperAdmin",
                                            null, new { @class = "btn btn-danger" })

                        <button type="button" onclick="clickMe()"
                                class="btn btn-danger">
                            Remove Role
                        </button>
                    </div>
                } [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult AssignAdmin(AssignRolesModel model)
        {
            try
            {
                if(model.lstUsers == null)
                {
                    TempData["Error"] = "There are no Users to Assign Roles";
                    model.lstUsers = UserList();
                    model.lstAdmins = AdminList();
                    return View(model);
                }

                var selectedUsersCount = (from user in model.lstUsers
                                          where user.SelectedUsers == true
                                          select user).Count();
                if(selectedUsersCount == 0)
                {
                    TempData["Error"] = "You have not Selected any User to Assign Roles";
                    model.lstAdmins = AdminList();
                    model.lstUsers = UserList();
                    return View(model);
                }

                if (ModelState.IsValid)
                {
                    List<UserModel> users = new List<UserModel>();
                    ApplicationUser au;
                    var store = new UserStore<ApplicationUser>(context);
                    var manager = new UserManager<ApplicationUser>(store);
                    model.CreatedBy = 1;

                    foreach(var u in model.lstUsers)
                    {
                        if(u.SelectedUsers == true)
                        {
                            users.Add(u);
                        }
                    }

                    foreach(var u in users)
                    {
                        au = context.Users.Where(x => x.Id.Equals(u.UserId,
                            StringComparison.CurrentCultureIgnoreCase)).FirstOrDefault();
                        manager.RemoveFromRole(au.Id, "User");
                        manager.AddToRole(au.Id, "Admin");
                    }

                    TempData["Success"] = "Roles Assigned Successfully";
                    return RedirectToAction("AssignAdmin");
                }
            }
            catch (Exception)
            {
                throw;
            }           

            return View();
        }    public class AdminModel
    {
        public string UserId { get; set; }
        public string Name { get; set; }
        public string Username { get; set; }
    }
    public class UserModel
    {
        public string UserId { get; set; }
        public string Name { get; set; }
        public string Username { get; set; }
        public bool SelectedUsers { get; set; }
        public string AssignToAdmin { get; set; }
    }
    public class AssignRolesModel
    {
        public List<AdminModel> lstAdmins { get; set; }
        [Required(ErrorMessage = "Choose Admin")]
        public string UserId { get; set; }
        public List<UserModel> lstUsers { get; set; }
        public int? AssignToAdmin { get; set; }
        public int? CreatedBy { get; set; }
    }