I have an entity model that has audit information on every table (50+ tables)

 CreateDate
 CreateUser
 UpdateDate
 UpdateUser

Currently we are programatically updating audit information.

Ex:

  if(changed){
        entity.UpdatedOn = DateTime.Now;
        entity.UpdatedBy = Environment.UserName;
        context.SaveChanges();
   }

But I am looking for a more automated solution. During save changes, if an entity is created/updated I would like to automatically update these fields before sending them to the database for storage.

Any suggestion on how i could do this?

Let me know if any more information is needed.