Entity Framework 6 one to many insert problem

Question

User777726829 posted

I am having an issue whenever I try to insert a one <g class="gr_ gr_106 gr-alert gr_gramm gr_inline_cards gr_run_anim Grammar multiReplace" id="106" data-gr-id="106">to</g> many <g class="gr_ gr_111 gr-alert gr_gramm gr_inline_cards gr_run_anim Grammar multiReplace" id="111" data-gr-id="111">relationship</g>. The record for the one table gets stored, however, nothing happens in the many <g class="gr_ gr_250 gr-alert gr_gramm gr_inline_cards gr_run_anim Grammar multiReplace" id="250" data-gr-id="250">table</g>. The relationship <g class="gr_ gr_470 gr-alert gr_gramm gr_inline_cards gr_run_anim Grammar multiReplace" id="470" data-gr-id="470">seem</g> to have been created successfully, as the foreign key (one table's primary key) is in the many <g class="gr_ gr_413 gr-alert gr_gramm gr_inline_cards gr_disable_anim_appear Grammar multiReplace" id="413" data-gr-id="413">table</g>.

I welcome any suggestion, as this problem is setting me back.

Thanks

Answer 1

User1120430333 posted

http://www.c-sharpcorner.com/UploadFile/d87001/connected-and-disconnected-scenario-in-entity-framework/

EF can be in one of two states. A Web application running on a Web server is stateless. Therefore  EF is being used in a Web application as a stateless solution. So, you must tell EF the entity's state when trying to persist it to the database.

Answer 2

User777726829 posted

Thanks for <g class="gr_ gr_12 gr-alert gr_gramm gr_inline_cards gr_run_anim Grammar multiReplace" id="12" data-gr-id="12">you</g> response. See code snippet below:

  public void SetAsAdded<TEntity>(TEntity entity) where TEntity : BaseEntity

        {

            UpdateEntityState(entity, EntityState.Added);

            

        }

 

 private void UpdateEntityState<TEntity>(TEntity entity, EntityState entityState) where TEntity : BaseEntity

        {

            var dbEntityEntry = GetDbEntityEntrySafely(entity);

            dbEntityEntry.State = entityState;

        }

        private DbEntityEntry GetDbEntityEntrySafely<TEntity>(TEntity entity) where TEntity : BaseEntity

        {

            var dbEntityEntry = Entry<TEntity>(entity);

            if (dbEntityEntry.State == EntityState.Detached)

            {

                Set<TEntity>().Attach(entity);

            }

            return dbEntityEntry;

        }

I did tell EF the state.

Answer 3

User1120430333 posted

http://www.entityframeworktutorial.net/EntityFramework5/add-entity-graph-using-dbcontext.aspx

<copied>

Add Entity Graph using DbContext:

The following example adds a student entity graph in disconnected mode, using the DbSet.Add() method which marks the added state to all the entities:

<end>

One of the pages in the above link shows how to do it.

Answer 4

User777726829 posted

Thanks a mil DA924! That approach worked.