ef 两表left join

linq写法：

//linq写法
var query = (from u in oae.Users
                join p in oae.User_Parent on u.Id equals p.UsersId into jointemp
                from leftjoin in jointemp.DefaultIfEmpty()
                select new UserViewModel
                {
                    UserName = u.UserName,
                    Father = leftjoin.Father,
                    Mother = leftjoin.Mother
                }).ToList();

lamdba写法：

//lamdba
var result = oae.Users.GroupJoin(oae.Score, a => a.Id, b => b.UsersId, (a, b) => new
                            {
                                UserName = a.UserName,
                                scoreList = b
                            }).SelectMany(a => a.scoreList.DefaultIfEmpty(), (a, b) => new
                            {
                                UserName = a.UserName,
                                Sub = b.Sub,
                                Score = b.Score1
                            }).ToList();

其他写法