我的模型对于ApplicationUser是空的

Question

我的模特为

 public class UserToRolesModel
{
    public List<ApplicationUser> userList { get; set; }
    public List<Microsoft.AspNet.Identity.EntityFramework.IdentityRole> rolesList { get; set; }

    [Required]
    public List<Microsoft.AspNet.Identity.EntityFramework.IdentityRole> selectedRoles { get; set; }
    [Required]
    public List<ApplicationUser> selectedUsers { get; set; }

}

视图为

    @model InventoryEasy15.Models.UserToRolesModel

@Html.ValidationSummary(true, "", new { @class = "text-danger" })
                        @Html.ListBoxFor(x => x.selectedRoles, new SelectList(Model.rolesList, "Id", "Name"), new { style = "width:100%", id = "Roles", @class = "select2", data_placeholder = "Select the Role" })
                        @Html.ValidationMessageFor(m => m.selectedRoles, "", new { @class = "text-danger" })

我在Post中得到的模型是空的。我的帖子是

[HttpPost]
    public ActionResult SaveUserRoles(UserToRolesModel usersroles)
    {
        foreach(var user in usersroles.selectedUsers)
        {
            var userExistingRoles = context.Roles;
        }
        return View(usersroles);
    }

get正确绑定数据，

public ActionResult AddUserToRole()
    {
        var model = new UserToRolesModel();
        var users = context.Users.ToList();
        model.userList = users;
        model.rolesList = context.Roles.ToList();
        return View(model);
    }

以前我遇到过问题，我将模型用于局部变量，导致了同样的问题。但我不认为这里有问题