var result = from u in db.Order join n in db.Equipment on u.OrderId equals n.OrderId into temp from m in temp.DefaultIfEmpty() select new { OrderID = u.OrderId, Customername = u.Customername, EId = m == null ? "" : m.EId.ToString(), Price = m == null ? 0 : m.Price };EntityFramework left join,布布扣,bubuko.com
原文：http://www.cnblogs.com/wolf12/p/3772971.html