C# Tuple<T1,T2....T>元组的使用

            //一个元素的元组
            Tuple<int> test = new Tuple<int>(34);

            //两个元素的元组 1<n<8
            Tuple<string, int> test2 = Tuple.Create<string, int>("str", 2);
            Tuple<int, int> test2_1 = new Tuple<int, int>(2,2);

            //8个元素的元组(注意，Tuple<类型...>： 基本"类型"最多7个， 第八个元素类型必须也为元组)
            Tuple<int, int, int, int, int, int, int, Tuple<int>> test3 = 
            new Tuple<int, int, int, int, int, int, int, Tuple<int>>(1, 2, 3, 4, 5, 6, 7, new Tuple<int>(8));
            
            //也可以这样
            Tuple<int, int, Tuple<int, int>> test_i_i_Tii = new Tuple<int, int, Tuple<int, int>>(1,1,new Tuple<int,int>(2,3));
            
            Console.WriteLine(test.Item1);
            Console.WriteLine(test2.Item1 + test2.Item2);
            Console.WriteLine(test2_1.Item1 + test2_1.Item2);
            Console.WriteLine(test3.Item1 + test3.Item2 + test3.Item3 + test3.Item4 + test3.Item5 + test3.Item6 + test3.Item7 + test3.Rest.Item1);

namespace TupleDemo
{
    class Program
    {
        static void Main(string[] args)
        {

            //使用out拿到多个返回值
            string outparam = "";
            int returnvalue = FunOutParamDemo(out outparam);
            Console.WriteLine(returnvalue + "    " + outparam);

            //使用元组拿到多个返回值
            Tuple<int, string> r = FunTupleParamDemo();
            Console.WriteLine(r.Item1 + "    " + r.Item2);

            Console.Read();
        }
        /// <summary>
        /// out关键字，实现返回两个返回值
        /// </summary>
        /// <param name="o"></param>
        /// <returns></returns>
        public static int FunOutParamDemo(out string o)
        {
            o = "returnValue";
            return 10;
        }

        /// <summary>
        /// 使用元组实现【间接】返回【两个】返回值
        /// </summary>
        /// <returns></returns>
        public static Tuple<int, string> FunTupleParamDemo() {
            return new Tuple<int, string>(10, "returnValue");
        }
    }
}