在Asp.Netmvc 5 EntityFramework 6中尝试为用户和角色种子数据时出错

当我尝试用用户和角色的种子数据更新数据库时，我得到一个"一个或多个实体的验证失败。有关更多详细信息，请参阅"EntityValidationErrors"属性。"错误。角色被创建了，我可以在db表中看到它们，但具有管理员角色的用户没有被创建。此外，角色不会显示在创建和编辑用户视图中。

创建用户的ViewModel：

public class InsertUser
{
    [Required]
    [StringLength(50, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 2)]
    [Display(Name = "First Name")]
    [RegularExpression(@"^[A-Z]+[a-zA-Z''-''s]*$", ErrorMessage = "The {0} must start with upper letter and contain only alphabetical letters")]//requires the first character to be upper case and the remaining characters to be alphabetical
    public string FirstName { get; set; }
    [Required]
    [StringLength(50, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 2)]
    [Display(Name = "Last Name")]
    [RegularExpression(@"^[A-Z]+[a-zA-Z''-''s]*$", ErrorMessage = "The {0} must start with upper letter and contain only alphabetical letters")]
    public string LastName { get; set; }
    [Required]
    [EmailAddress]
    [Display(Name = "Email")]
    public string Email { get; set; }
    [Display(Name = "User Name")]
    public string UserName { get; set; }
    [Required]
    [StringLength(100, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 6)]
    [DataType(DataType.Password)]
    [Display(Name = "Password")]
    public string Password { get; set; }
    [DataType(DataType.Password)]
    [Display(Name = "Confirm new password")]
    [Compare("Password", ErrorMessage = "The new password and confirmation password do not match.")]
    public string ConfirmPassword { get; set; }
    public List<CheckBoxItem> Roles { get; set; }
}
public class CheckBoxItem
{
    public string Id { get; set; }
    public string Text { get; set; }
    public bool Checked { get; set; }
}

编辑用户的ViewModel：

public class EditUser
{
    public EditUser()
    {
        Roles = new List<CheckBoxItem>();
    }
    [Key]
    public string Id { get; set; }
    [Display(Name = "User Name")]
    public string UserName { get; set; }
    [Required]
    [StringLength(50, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 2)]
    [Display(Name = "First Name")]
    [RegularExpression(@"^[A-Z]+[a-zA-Z''-''s]*$", ErrorMessage = "The {0} must start with upper letter and contain only alphabetical letters")]
    public string FirstName { get; set; }
    [Required]
    [StringLength(50, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 2)]
    [Display(Name = "Last Name")]
    [RegularExpression(@"^[A-Z]+[a-zA-Z''-''s]*$", ErrorMessage = "The {0} must start with upper letter and contain only alphabetical letters")]
    public string LastName { get; set; }
    [Required]
    [EmailAddress]
    [Display(Name = "Email")]
    public string Email { get; set; }        
    public List<CheckBoxItem> Roles { get; set; }
}

我创建了自己的ViewModel来编辑和创建用户，因为场景是这样的，用户必须从管理员那里创建，所以为了保持分离，我创建了我自己的ViewModels，不同于AccountViewModel。但除此之外，一个简单的用户可以在ASp.NetMVC中使用个人用户帐户、电子邮件、用户名和密码创建，就像开箱即用一样。管理员有权添加更多详细信息，如FirstName和LastName，并分配角色。

创建（和编辑）视图：

...
 <div class="form-group">
        @Html.LabelFor(model => model.Roles, new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.CheckBoxListFor(model => model.Roles
            , model => model.Roles
            , model => model.Id
            , model => model.Text
            , model => model.Checked
            , model => new { @class = "checkbox-inline" })
        </div>
    </div>
...

我为ChechBoxListFor html助手安装了MvcCheckBoxList nuget。

创建用户的get操作方法：

public ActionResult Create()
    {
        var items = new InsertUser();
        items.Roles = _roleManager.Roles.Select(x => new CheckBoxItem { Id = x.Id, Text = x.Name, Checked = false }).ToList();
        return View(items);
    }

和配置类，种子方法：

if (!context.Roles.Any(r => r.Name == "admin"))
        {
            var store = new RoleStore<IdentityRole>(context);
            var manager = new RoleManager<IdentityRole>(store);
            var role = new IdentityRole { Name = "admin" };
            manager.Create(role);
        }
        if (!context.Roles.Any(r => r.Name == "user"))
        {
            var store = new RoleStore<IdentityRole>(context);
            var manager = new RoleManager<IdentityRole>(store);
            var role = new IdentityRole { Name = "user" };
            manager.Create(role);
        }
        if (!context.Users.Any(u => u.UserName == "admin"))
        {
            var store = new UserStore<ApplicationUser>(context);
            var manager = new UserManager<ApplicationUser>(store);
            var user = new ApplicationUser { UserName = "admin", Email="admin@email.com" };
            manager.Create(user, "password123");
            manager.AddToRole(user.Id, "admin");
        }

仅供参考，我将密码设置为至少需要6个字母，我评论了其他请求，如RequiredLowercase、RequieredUppercase、RequireOnLetterOrDigit、RequireDigit。

那么，有人能帮我解决这个问题吗，创建管理员用户，并在编辑和创建视图中显示角色？