[LINQ]多条件关联

多条件关联：

var data = (from h in context.FT_LY join d in context.FT_LY_Detail on new { h.Company, h.LYNo } equals new { d.Company, d.LYNo } where (h.LYDate>=_DateStart) && (h.LYDate<=_DateEnd) && (h.Company==MyCompany) && (string.IsNullOrEmpty(_LYNo) || h.LYNo == _LYNo) && (string.IsNullOrEmpty(_Item) || d.Item == _Item) && (string.IsNullOrEmpty(_ItemName) || d.ItemName == _ItemName) && (string.IsNullOrEmpty(_ItemSpec) || d.ItemSpec == _ItemSpec) select new { h.Company, h.LYNo, h.LYDate, h.LYUser, h.DeptName, h.Creater, h.Remark, h.Audit, h.Auditor, h.AuditDate }); this.gdMain.DataSource = data.ToList().Distinct();