linq语法

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List<C01Dog> list = GetDogList();

//9.1 从老集合中查询每一个元素(d) 存入新集合
var dogs1 = from d in list select d;

//forech(var d in list)循环这个集合

//9.2 where条件从老集合中查询所有 Gender = falser 的元素，存入新集合
//var dogs2 = select d from d in list where d.Gender == false ;
var dogs2 = from d in list where d.Gender == false select d;

List<C01Dog> list = GetDogList();            List<C02DogToy> listToys = GetDogToyList();            //9.1 从 老集合中 查询 每一个 元素(d) 存入 新集合            var dogs1 = from d in list select d;            //9.2 where条件 从 老集合中 查询 所有 Gender = falser 的 元素，存入 新集合            //var dogs2 = select d from d in list where d.Gender == false ;            var dogs2 = from d in list where d.Gender == false select d;            //9.3 排序条件            var dogs3 = from a in list orderby a.Age orderby a.ID orderby a.Name descending select a;            //9.4 连接查询 注意：连接条件 使用  equals 关键字！！！//返回的是新的匿名类            var joinedList = from a in list join t in listToys on a.ID equals t.DogID select new { Dog = a, Toy = t };            foreach (var item in joinedList)            {                Console.WriteLine(item.ToString());            }            Console.WriteLine("分组啦~~~-----------------------");            //9.5 分组查询            var groupList = from d in list group d by d.Gender;            foreach (var group in groupList)            {                Console.WriteLine(group.Key.ToString());                foreach (var item in group)                {                    Console.WriteLine(item.ToString());                }            }