c# - EF - Update multiple rows in database without using foreach loop

Question

My test code:

using (var db = new MyDbContext())
{
  string fromUser = ""; //sender
  string toUser = ""; //receiver

  var messages = db.Message.Where(x => x.FromUser == fromUser && x.ToUser == toUser)
                 .ToList();

  foreach (var message in messages)
  {
    message.IsRead = true;
    db.SaveChanges();
  }
}

My question: is there another way to update database without using foreach loop in that case?

p/s: I'd been reference these questions but all of them didn't solve my problem:

• Update multiple rows in datatable without loop

• updating multiple records in database with linq to sql without loop, is it possible?

• Update multiple rows without looping

Answer 1

You don't need to SaveChanges() on each iteration. That will hit the database multiple times. Try:

using (var db = new MyDbContext())
{
  string fromUser = ""; //sender
  string toUser = ""; //receiver
  var messages = db.Message.Where(x => x.FromUser == fromUser && x.ToUser == toUser)
                 .ToList();
  messages.ForEach(m => m.IsRead = true);
  db.SaveChanges();
}