Question

当Dbcontext的任何实体中发生任何实体验证错误时，它在当前上下文中将持续存在。如果我们下次为任何操作（添加，更新或删除）传递有效数据，则先前的验证错误仍然存在，此后将不处理任何操作。我认为这是一个错误。如果传递了新数据，则应将其删除。如何从当前上下文中删除该验证错误？

Answer 1

当我们将实体添加到集合时，将其添加到其本地存储中，并且由于该实体的本地存储不清晰并且在那里仍然有旧条目，我们一直收到错误消息。因此，您必须从当前上下文中删除那些验证错误。您可以查看以下链接以了解更多详细信息：http://www.binaryintellect.net/articles/c1bff938-1789-4501-8161-3f38bc465a8b.aspx

if(ex is DbEntityValidationException dbException)
  {                 

   foreach (var eve in dbException.EntityValidationErrors)
    {                    
                    foreach (var ve in dbException.EntityValidationErrors.SelectMany(entity => entity.ValidationErrors))
                    {
                        sbErrorList.AppendLine(
                                                String.Format(" Entity: \"{0}\", Action: \"{1}\", Property: \"{2}\", Value: \"{3}\", Error: \"{4}\"",
                                                eve.Entry.Entity.GetType().Name, 
                                                eve.Entry.State,
                                                ve.PropertyName,
                                                eve.Entry.CurrentValues.GetValue<object>(ve.PropertyName),
                                                ve.ErrorMessage)
                                               );
                    }

                    #region Removing Entity Validation Error from current context : Rollback Changes                       


                    // checks the State property of the DbEntityEntry causing the error
                    switch (eve.Entry.State)
                    {
                        case EntityState.Added:
                            eve.Entry.State = EntityState.Detached; // changed to Detached so that the entry won't be considered a part of the DbSet for future calls
                            break;
                        case EntityState.Modified:
                            eve.Entry.CurrentValues.SetValues(eve.Entry.OriginalValues); // the modified values (the values causing the error) are flushed out by replacing them with the OriginalValues.
                            eve.Entry.State = EntityState.Unchanged;
                            break;
                        case EntityState.Deleted:
                            eve.Entry.State = EntityState.Unchanged; // changed to Unchanged so that the entity is undeleted
                            break;
                    }
                    #endregion
                }                   
            }

Microsoft实体验证错误删除

1 个答案: