Linq查询 group into

            Student[] stuArray =
            {
                new Student("chandler",20,"男"),
                new Student("joe",39,"男"),
                new Student("rose",38,"男"),
                new Student("monica",28,"女"),
                new Student("rachel",27,"女"),
                new Student("phobee",27,"女")


            };


            var query = from st in stuArray group st by st.Age into temp orderby temp.Key descending select temp;
            foreach (var item in query)
            {
                Console.WriteLine(item.Key+"岁的人");
                foreach (var i in item)
                {
                    Console.WriteLine(i.Name + "-" + i.Age + "-" + i.Sex);
                }
            }