EF Core: Built in Created and Edited timestamps [duplicate]

Question

The title is quite self-explanatory. Is there a built-in mechanism to support Created and Edited timestamps on records in a code-first database in Entity Framework Core?

Something like :created_at and :updated_at in Ruby on Rails migrations. I could not find any documentation concerning this. If no out-of-the-box mechanism is present, is there a best practice how to implement those columns?

Answer 1

The non EF Core solutions don't apply to EF Core without some amount of rework. I wanted to allow certain entities to have CreatedAt and LastModified timestamps that updated in a reasonably automated way. This is what I ended up doing.

1. Defined an interface - ITimeStampedModel that my models could inherit from that required them to have the timestamps I wanted:

   public interface ITimeStampedModel
   {
       DateTime CreatedAt {get; set;}
       DateTime LastModified {get; set;}
   }
   

2. Override SaveChanges on my DbContext to look for new or modified models, and update their timestamps appropriately:

   public override int SaveChanges()
   {
       var newEntities = this.ChangeTracker.Entries()
           .Where(
               x => x.State == EntityState.Added &&
               x.Entity != null &&
               x.Entity as ITimeStampedModel != null
               )
           .Select(x => x.Entity as ITimeStampedModel);
   
       var modifiedEntities = this.ChangeTracker.Entries() 
           .Where(
               x => x.State == EntityState.Modified &&
               x.Entity != null &&
               x.Entity as ITimeStampedModel != null
               )
           .Select(x => x.Entity as ITimeStampedModel);
   
       foreach (var newEntity in newEntities)
       {
           newEntity.CreatedAt = DateTime.UtcNow;
           newEntity.LastModified = DateTime.UtcNow;
       }
   
       foreach (var modifiedEntity in modifiedEntities)
       {
           modifiedEntity.LastModified = DateTime.UtcNow;
       }
   
       return base.SaveChanges();
   }
   

Anyone have a better solution?