验证失败后用DbEntityValidationException 查找出错的字段

           try

            {

                // Your code...

                // Could also be before try if you know the exception occurs in SaveChanges

                int effect = await _unitOfWorkAsync.SaveChangesAsync();

            }

            catch (System.Data.Entity.Validation.DbEntityValidationException e)

            {

                foreach (var eve in e.EntityValidationErrors)

                {

                    Console.WriteLine("Entity of type \"{0}\" in state \"{1}\" has the following validation errors:",

                        eve.Entry.Entity.GetType().Name, eve.Entry.State);

                    foreach (var ve in eve.ValidationErrors)

                    {

                        Console.WriteLine("- Property: \"{0}\", Error: \"{1}\"",

                            ve.PropertyName, ve.ErrorMessage);

                    }

                }

                throw;

            }