Join nhiều điều kiện

var list = (from p in db.xkXuatKhos

                                join ct in db.xkTaiSans on p.MaXK equals ct.MaXK

                                join bh in db.xkBanHangs on p.MaBanHang equals bh.MaBH

                                join bhvt in db.xkBanHang_VatTus on  ( bh.MaBH+"&"+ ct.MaLTS ) equals (  bhvt.MaBH+"&"+  bhvt.MaLTS )

                                join ts in db.tsLoaiTaiSans on ct.MaLTS equals ts.MaLTS

                                join dvt in db.tsLoaiTaiSan_DVTs on ts.MaDVT equals dvt.MaDVT

                                where p.MaXK == maXK

                                select new

                                {

                                    ts.TenLTS,

                                    ts.KyHieu,

                                    dvt.TenDVT,

                                    SoLuongYeuCau=bhvt.SoLuongQuyDoi-bhvt.SoLuongDaXuatKho+ct.SoLuong,

                                    SoLuongThucXuat=ct.SoLuong,

                                    DonGia=ct.DonGia,

                                    ThanhTien=ct.SoLuong*ct.DonGia

                                }).AsEnumerable().Select((p, Index) => new

                                {

                                    STT = Index + 1,

                                    p.TenLTS,

                                    p.KyHieu,

                                    p.TenDVT,

                                    p.SoLuongYeuCau,

                                    p.SoLuongThucXuat,

                                    p.DonGia,

                                    p.ThanhTien

                                }).ToList();