Entity framework update no tracking entity

Question

How can I update an entity that is detached from context by AsNoTracking()?

var _agency = agencyRepository.Get(filter: a => a.Id == agency.Id)
                              .AsQueryable()
                              .AsNoTracking()
                              .FirstOrDefault(); 
agencyRepository.Update(_agency);

and my Update method already set modified:

public virtual void Update(T entity)
    {            
        dbset.Attach(entity);
        dataContext.Entry(entity).State = System.Data.Entity.EntityState.Modified;
    }

Can I find the previous entity that is attached by datacontext? or any suggestion to prevent Tracking on my User entity?

Answer 1

you can change the state of the entity:

ctx.Entry(_agency).State = System.Data.Entity.EntityState.Modified;
ctx.SaveChanges();

More Read this or this article.

Answer 2

When you get your object as "AsNoTracking", it means that it's detached from the context and changes won't be tracked. All you need to do is attach it to the context again.

Here is a sample code:

async Task update_entity() {
  ctx.Attach(profile);
  profile.image_id = "12345667";
  await ctx.SaveChangesAsync();
}