Using Include in Entity Framework 4 with lambda expressions

Question

I\'ve seen many articles about how to overcome this matter, all related to CTP4, Or adding my own extension methods.

Is there an \"official\" EF4 included way to use

Answer 1

The RTM version of Entity Framework 4.1 actually includes extension methods in the EntityFramework.dll file, for eager loading with lambda through the Include function. Just include the DLL in your project and you should be able to write code like:

var princesses1 = context.Princesses.Include(p => p.Unicorns).ToList();

Remember to add an Import/Using statement to include the System.Data.Entity namespace. Otherwise the compiler cannot find the extension methods. E.g:

using System.Data.Entity;

See this ADO.NET team blog article for more information.