c#中分支语句的运用:

using System;
using System.Collections.Generic;
using System.Text;
namespace ConsoleApplication9
{

    class Program
    {
        static void Main(string[] args)
        {
            //int x = 5;
            //int y = 3;
            //// & | ^ ~

            ////&两个都是一才为１
            //int z = x & y;
            ////x=0101
            ////y=0011
            ////&-----------
            ////z=0001(2)
            //Console.WriteLine(z);

            ////|两个有一个为一就为１
            //z = x | y;
            ////x=0101
            ////y=0011
            ////z=0111(7)
            //Console.WriteLine(z);

            ////^两个不同就为１
            //z = x ^ y;
            ////x=0101
            ////y=0011
            ////z=0110(6)
            //Console.WriteLine(z);

            ////~一元运算符相反值
            //z = ~x;
            ////x=0101
            ////z=1010(-6)
            //Console.WriteLine(z);

            //z = x >> 2;
            ////x=0101
            ////z=0001(1)
            //Console.WriteLine(z);

            //z = x << 2;
            ////x=00000101
            ////z=00010100
            //Console.WriteLine(z);
            //int x = 5;
            //Console.WriteLine(x==5?"x=5":"x!=5");

            //int x = 5;
            //int y = 6;
            //string str;
            //str = x == y ? "等于" : "不等于";
            //Console.WriteLine(str);
            //int y = 5;
            //if (y == 5)
            //{
            //    Console.WriteLine("y=5");
            //}
            int x = 0;
            lba:
            Console.WriteLine("你喜欢吃什么？A:苹果;B:香蕉;C:梨子");
            switch (Console.ReadLine().ToUpper())
            {
                case "A":
                    Console.WriteLine("你喜欢吃苹果！");
                    break;
                case "B":
                    Console.WriteLine("你喜欢吃香蕉！");
                    break;
                case "C":
                    Console.WriteLine("你喜欢吃梨子！");
                    break;
                default:
                    Console.WriteLine("你真够馋的！");
                    break;

            }
            Console.WriteLine();
            Console.WriteLine("还选吗？A:断续B:不选");
            if (Console.ReadLine().ToUpper()=="A")
            {
                if (x>2)
                {
                    Console.WriteLine("还吃呀撑死你！");
                    return;
                }
                x++;
                goto lba;
            }

        }
    }
}