EF 6更新实体时行为异常

Question

I have an entity that has a list of events attached to itself... think of it as a list of "what happened to me"...

Every event has a SourceUser which is an entity also...

The thing is: when I try to update an entity, a new event is created and the current user is stamped on this event, and when I call Update , EF 6 does not see the user as a existing user (I think it's recognizing it as new) and it's trying to insert it, which causes a primary key violation...

How can I handle this? How can I tell EF that the event is new, but it's associated entities are not new?!?

EDIT1:
@Jonesy I inherited this code and (except for keywords) it's in portuguese so i dont think it's gonna make much sense but i can explain it! Here: When the user sends a request, i grab a token, and retrive the user from the database via authentication-filter and build a "context" object that has a "CurrentUser"... when creating the event, i just grab "CurrentContext.CurrentUser"...

Answer 1

This issue presents itself when you are dealing with disconnected/detached Entity Framework POCO objects,. as the DbContext doesn't track changes to entities. Specifically, trouble occurs with entities participating in a many-to-many relationship, where the EF has hidden a “join table” from the model itself.

The problem with detached entities is that the data context has no way of knowing what changes have been made to an object graph, without fetching the data from the data store and doing an entity-by-entity comparison – and that assuming it's possible to fetch the same way as it was originally.

This links may help you:

Why Does Entity Framework Reinsert Existing Objects into My Database?

Solving the detached many-to-many problem with the Entity Framework