同时加载多级关联实体

 

 using (var context = new UnicornsContext())
{
    // Load all castles, all related ladies-in-waiting, and all related
    // princesses
    var castles1 = context.Castles
                       .Include(c => c.LadiesInWaiting.Select(b => b.Princess))
                       .ToList();

    // Load all unicorns, all related princesses, and all related ladies
    var unicorns1 = context.Unicorns
                        .Include(u => u.Princess.LadiesInWaiting)
                        .ToList();

    // Load all castles, all related ladies, and all related princesses
    // using a string to specify the relationships
    var castles2 = context.Castles
                       .Include("LadiesInWaiting.Princess")
                       .ToList();

    // Load all unicorns, all related princesses, and all related ladies
    // using a string to specify the relationships
    var unicorns2 = context.Unicorns
                        .Include("Princess.LadiesInWaiting")
                        .ToList();
}

Note that it is not currently possible to filter which related entities are loaded.