public Guid?GetManagerID(Employee employee) { Guid dptid = employee.DepartmentID; Guid rankid = new RankDAL().GetRankIDByRankName("Manager"); DataTable dt = SqlHelper.ExecuteDataTable("select * from T_Employee where DepartmentID =@DepartmentID and RankID = @RankID and IsDeleted = 0", new SqlParameter("@DepartmentID", dptid), new SqlParameter("@RankID", rankid)); if (dt.Rows.Count == 1) { Employee manager = ToModel(dt.Rows[0]); return(manager.ID); } else { return(null); } }