Lost in EF for disconnect CRUD

Question

I am completely lost why this error suddenly started coming.

I had Entity A which has one to Many relations with Entity B. It was working very nice but suddenly it stopped working. I can't even add/update an item in Enitity A nor i can't add/update in entity B. Only Get works fine. If i do Add or update for anything in there i get below error.

Have almost tried all the suggestion from stack overflow but nothing works.

The operation failed: The relationship could not be changed because one or more of the foreign-key properties is non-nullable. When a change is made to a relationship, the related foreign-key property is set to a null value. If the foreign-key does not support null values, a new relationship must be defined, the foreign-key property must be assigned another non-null value, or the unrelated object must be deleted.

     public class ReportCategory : BaseEntity
     {
          public string Name { get; set; }

          public List<ReportType> ReportTypes { get; set; }
     }

     public class ReportType : BaseEntity
     {
            public string Name { get; set; }

           public int ReportCategoryId { get; set; }

         public string ReportUrl { get; set; }

         public ReportCategory ReportCategory { get; set; }

           public List<ReportAccess> reportAccesses { get; set; }

        }

entity add operation

        public void Add(T entity)
    {
        if (entity == null)
        {
            throw new ArgumentNullException("entity");
        }
        entities.Add(entity);
        context.SaveChanges();
    }

update operation

           public void Update(T entity)
    {
        if (entity == null)
        {
            throw new ArgumentNullException("entity");
        }
        if (entity.Id == 0)
        {
            throw new Exception("Entity unidentified");
        }
        if (entities.Local.Any(d => d.Id == entity.Id))
        {
            context.Entry(entities.Local.First(d => d.Id == entity.Id)).State = EntityState.Detached;
        }
        entities.Attach(entity);
        context.Entry(entity).State = EntityState.Modified;
        //entities.Attach(entity);
        context.SaveChanges();
    }

I would really appreciate if someone could help with this.

Did you change code or something in the database? Did you verify the data in the tables? And what did you try, can you be more specific? — , May 03 '17 at 21:42
This may help: http://stackoverflow.com/questions/5538974/the-relationship-could-not-be-changed-because-one-or-more-of-the-foreign-key-pro — Eric Yeoman, May 03 '17 at 21:49
So i am trying to add simple item in entity A which doesn't work and throws the error which i mentioned. About the data everything looks good in the tables. But still figuring out what the problem is here. — Dharmen Bavaria, May 03 '17 at 21:52
@Eric Yeoman already tried that link and also other but nothing works. — Dharmen Bavaria, May 03 '17 at 21:54
@RuardvanElburg actually its very simple code for just add into the context.a.add(entity) but it doesn't work for every entities not only for A but also for B. I am not sure what is happening here but i am in big problem i dont know what to do someone's help would be helpful — Dharmen Bavaria, May 03 '17 at 22:08
@RuardvanElburg I have updated questions. I hope that helps. — Dharmen Bavaria, May 03 '17 at 22:24
Which approach did you adopt? Code first, model first or database first? — FortyTwo, May 03 '17 at 23:08
@DharmenBavaria ReportType is owned by ReportCategory right? If so do you have cascade delete enabled? Also, have you tried connecting to another fresh instance of db and run your application? — FortyTwo, May 04 '17 at 08:51
thank you everyone i think i found my solution. It was something with context instance which was messing up. — Dharmen Bavaria, May 05 '17 at 14:19

Lost in EF for disconnect CRUD

0 Answers0