Intercept saving of entities in Entity Framework Core

Question

Is there a way for EF Core to intercept the pre insertion, pre update, pre delete, post insert, post update and post delete events of an entity?

EF core supports interceptors, but I think it's more focused on logging queries https://www.entityframeworktutorial.net/entityframework6/database-command-interception.aspx

I'm looking for a feature like this https://github.com/khellang/EF.Interception

Answer 1

You already have a class that extends DbContext. Override the SaveChanges methods and you can examine the contents of the ChangeTracker to handle all your pre- event needs;

        private void PreSave()
        {
            foreach (var entry in ChangeTracker.Entries())
            {
                switch (entry.State)
                {...}
            }
        }

        public override async Task<int> SaveChangesAsync(bool acceptAllChangesOnSuccess, CancellationToken cancellationToken = default(CancellationToken))
        {
            PreSave();
            return await base.SaveChangesAsync(acceptAllChangesOnSuccess, cancellationToken);
        }

        public override int SaveChanges(bool accept) {
            PreSave();
            return base.SaveChanges(accept);
        }