【Language】C#之旅_③_条件语句

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namespace ConsoleApplication1
{
    class Program
    {
        enum hobby { reading,writing,singing,dancing }
        static void Main(string[] args)
        {
                     /*条件语句*/
            int month;
            month=0;
            /*if 语句*/
                //①语法—if(布尔值) 程序语句
                if (month < 1)
                {
                     Console.WriteLine("月份不存在!");
                }
                //②语法—if(布尔值) 程序语句a else 程序语句b
                month++;
                if (month == 1)
                {
                    Console.WriteLine("现在是一月");
                    month++;
                }
                else
                {
                    Console.WriteLine("月份不存在!");
                }
                //③语法—if(布尔值) 程序语句a else if 程序语句b else if 程序语句c … …
             
                if (month == 1)
                {
                    Console.WriteLine("现在是一月");
                }
                else if (month == 2)
                {
                    Console.WriteLine("现在是二月");
                }
                else if (month == 3)
                {
                    Console.WriteLine("现在是三月");
                }
                else
                {
                    Console.WriteLine("月份不存在!");
                }
                //当然还可以同时使用多个布尔值或者是上一小节的三元运算符(?:)

            /*switch 语句*/
                //语法:
                //switch (参数)
                //  {
                //      case 对应的参数值a:操作a;break;
                //      case 对应的参数值b:操作b;break;
                //      default:默认操作c;break;
                //  }
                int x=0;
                switch (x)
                {
                    case 0: Console.WriteLine("x的值是:0"); break;
                    case 1: Console.WriteLine("x的值是:1"); break;
                    default: Console.WriteLine("默认执行该情况"); break;
                }

                hobby myHobby = hobby.dancing;//枚举类型的使用——没忘了在开头定义的枚举类型的参数hobby吧?
                switch (myHobby)
                {
                    case hobby.dancing: Console.WriteLine("我喜欢的是跳舞吖!"); break;
                    case hobby.reading: Console.WriteLine("我喜欢的是读书啊!"); break;
                    case hobby.singing: Console.WriteLine("我喜欢的是唱歌啊!"); break;
                    case hobby.writing: Console.WriteLine("我喜欢的是写作哦!"); break;
                    default: Console.WriteLine("这些都不是我的爱好!"); break;
                }
               
                switch (myHobby)    //组合case的使用
                {
                    case hobby.dancing:
                    case hobby.reading: Console.WriteLine("我喜欢的是读书and跳舞啊!"); break;
                    case hobby.singing:
                    case hobby.writing: Console.WriteLine("我喜欢的是写作and唱歌哦!"); break;
                    default: Console.WriteLine("这些都不是我的爱好!"); break;
                }
  
            Console.ReadKey();//等待user输入
        }
    }
}