private void AuditEntities()
 {
     foreach (EntityEntry <IAuditable> entry in ChangeTracker.Entries <IAuditable>())
     {
         if (entry.State == EntityState.Added)
         {
             entry.Property("CreatedById").CurrentValue = _userResolverService.GetCurrentUserId();
             entry.Property("CreatedAt").CurrentValue   = DateTime.Now;
         }
         else if (entry.State == EntityState.Modified)
         {
             entry.Property("UpdatedById").CurrentValue = _userResolverService.GetCurrentUserId();
             entry.Property("UpdatedAt").CurrentValue   = DateTime.Now;
         }
     }
 }