在EF4.1中正确地从上下文中附加和分离实体

using (var context = new MyEntities())
{
    var newEntity = new MyEntity { Property1 = "Value1", Property2 = "Value2" };
    context.AddToMyEntities(newEntity);
    context.SaveChanges();
}

using (var context = new MyEntities())
{
    var entityToDetach = context.MyEntities.FirstOrDefault(e => e.Id == 1);
    if (entityToDetach != null)
    {
        context.Detach(entityToDetach);
    }
}

using (var context = new MyEntities())
{
    var entityToDelete = context.MyEntities.FirstOrDefault(e => e.Id == 1);
    if (entityToDelete != null)
    {
        context.DeleteObject(entityToDelete);
        context.SaveChanges();
    }
}