示例#1
0
        private static void TestSchoolDbAccess()
        {
            var db           = new SchoolEntities();
            var isAnyStudent = db.student.Any();

            Console.WriteLine(isAnyStudent);
        }
示例#2
0
        static void Main(string[] args)
        {
            //TestSchoolDbAccess();

            Console.WriteLine("*********************** ex 1");
            using (var db = new SchoolEntities())
            {
                db.Database.Log = logRecord => Console.WriteLine(logRecord);

                List <standard> standardList = db.standard.ToList();

                //List<string> standardStringList = standardList.Select(x => x.ToString()).ToList();
                //string standardListText = string.Join(Environment.NewLine, standardStringList);
                //Console.WriteLine(standardListText);

                ConsoleWriteList(standardList);
            }


            Console.WriteLine("*********************** ex 2");
            using (var db = new SchoolEntities())
            {
                db.Database.Log = logRecord => Console.WriteLine(logRecord);

                standard firstStandard = db.standard.Single(s => s.StandardId == 1);
                Console.WriteLine(firstStandard);

                List <teacher> firstStandardTeacherList = db.teacher.Where(t => t.StandardId == 1).ToList();
                ConsoleWriteList(firstStandardTeacherList);

                ConsoleWriteList(firstStandard.teacher.ToList());
            }

            Console.WriteLine("******************* ex 3");

            using (var db = new SchoolEntities())
            {
                db.Database.Log = logRecord => Console.WriteLine(logRecord);

                standard firstStandard = db.standard.
                                         Include(s => s.teacher).
                                         Single(s => s.StandardId == 1);

                Console.WriteLine(firstStandard);
                ConsoleWriteList(firstStandard.teacher.ToList());
            }

            Console.WriteLine("******************* ex 4");
            using (var db = new SchoolEntities())
            {
                db.Database.Log = logRecord => Console.WriteLine(logRecord);

                var q =
                    from s in db.standard
                    join t in db.teacher
                    on s.StandardId equals t.StandardId
                    where s.StandardId == 1
                    select new { s, t };
                var qList = q.ToList();

                ConsoleWriteList(qList.Select(x => x.s).Distinct().ToList());
                ConsoleWriteList(qList.Select(x => x.t).ToList());
            }
        }