c# - EntityFramework.dll 中发生类型为 'System.Data.Entity.Validation.DbEntityValidationException' 的第一次机会异常

Question

我在执行这段代码时收到这个错误:

[HttpPost]
        public ActionResult Registration(UserModel user)
        {
            Console.WriteLine("ja");
            try
            {

                if (ModelState.IsValid)
                {
                    var crypto = new SimpleCrypto.PBKDF2();
                    var encrpPass = crypto.Compute(user.Password);
                    UserModel newUser = new UserModel(user.Email, encrpPass);
                    newUser.PasswordSalt = crypto.Salt;

                    userRepository.Add(newUser);
                    userRepository.SaveChanges();

                    return RedirectToAction("Index", "Home");
                }
            }
            catch (System.Data.Entity.Validation.DbEntityValidationException ex)
            {

                    Console.WriteLine(ex);
            }


            return View(user);
        }

用户模型类:

public class UserModel
    {
        public int UserModelId { get; set; }
        [Required]
        [EmailAddress]
        [StringLength(150)]
        [Display(Name="Email address: ")]
        public String Email { get; set; }
        [Required]
        [DataType(DataType.Password)]
        [StringLength(20, MinimumLength = 6)]
        [Display(Name = "Password: ")]
        public String Password { get; set; }
        public String PasswordSalt { get; set; }

        public UserModel(String email, String password)
        {
            this.Email = email;
            this.Password = password;
        }

        public UserModel()
        {
        }
    }

有关异常的更多详细信息:

Message "OriginalValues cannot be used for entities in the Added state." string

堆栈跟踪:

StackTrace " bij System.Data.Entity.Internal.InternalContext.SaveChanges()\r\n bij System.Data.Entity.Internal.LazyInternalContext.SaveChanges()\r\n
bij System.Data.Entity.DbContext.SaveChanges()\r\n bij SoccerManager1.Models.DAL.UserRepository.SaveChanges() in d:\Stijn\Documenten\Visual Studio 2013\Projects\SoccerManager1\SoccerManager1\Models\DAL\UserRepository.cs:regel 48\r\n bij SoccerManager1.Controllers.UserController.Registration(UserModel user) in d:\Stijn\Documenten\Visual Studio 2013\Projects\SoccerManager1\SoccerManager1\Controllers\UserController.cs:regel 72" string

我只是想创建一个注册页面，我不明白为什么会收到此错误。

我在这里做错了什么？如果我提供的信息还不够，请告诉我。

Answer 1

您的某个属性值的验证可能失败。可能是您已将“StringLength”设置为 20 的密码，并且您正在插入加密密码。或者可能不会为某些非空字段传递值。

为了调试和查找实际原因，您可以在 catch 中使用以下代码块:

catch (System.Data.Entity.Validation.DbEntityValidationException ex)
{
    foreach (var validationErrors in ex.EntityValidationErrors)
    {
        foreach (var validationError in validationErrors.ValidationErrors)
        {
            Console.WriteLine("Property: {0} throws Error: {1}", validationError.PropertyName, validationError.ErrorMessage);
        }
    }
}