How to update related entities in Entity Framework

Question

I have an MVC project and using Entity Framework Code First and POCO objects for the database. For example:

public class ClassA
{
  public int? Id {get; set;         


        

Answer 1

If you attach and then set the state to modified entity framework will send all properties for update. You don't have to take the otter approach here below as that causes a whole separate load to occur. If you do it that way theres no sense in passing in a model, only an id and then you call TryUpdateModel to fill in the properties from the form.

Personally the attach as modified here is a bit cleaner as it doesn't require a complete round trip because of loading data

http://geekswithblogs.net/michelotti/archive/2009/11/27/attaching-modified-entities-in-ef-4.aspx