You are implementing an ASP.NET application that uses LINQ to Entities to access and update the
database. The application includes the following method to update a detached entity of type Person.
private NorthwindContext _entities;
public void UpdatePerson(Person personToEdit)
{
}
You need to implement the UpdatePerson method to update the database row that corresponds to
the personToEdit object.
Which code segment should you use?
A.
_entities.People.Attach(personToEdit);
_entities.ObjectStateManager.ChangeObjectState(
personToEdit,
EntityState.Modified);
_entities.SaveChanges();
B.
_entities.ObjectStateManager.ChangeObjectState(
personToEdit,
EntityState.Added);
_entities.SaveChanges();
C.
_entities.People.ApplyCurrentValues(personToEdit);
_entities.SaveChanges();
D.
_entities.People.Attach(new Person() { Id = personToEdit.Id }); _entities.ObjectStateManager.
ChangeObjectState(
personToEdit,
EntityState.Modified);
_entities.SaveChanges();
Explanation:
Table(Of TEntity).Attach Method (TEntity)
(http://msdn.microsoft.com/en-us/library/bb300517.aspx)