c#复杂数据类型的学习

枚举

使用

 public enum Day
        {
            mon,
            fri,
            wes,
            thr,
            thu,
            sat,
            sun
        }

类型转换

int转为枚举

           #region//将int类型转为枚举
            //int n1 = 1;
            //Day dayss=(Day)n1;
            //Console.WriteLine(dayss);
            //Console.ReadKey();
            #endregion

枚举转为int

 #region//将枚举类型转为int类型

            //Day days = Day.mon;
            int n = 10;
            //int n=(int)days;
            //Console.WriteLine(n);
            //Console.WriteLine((int)Day.fri);
            //Console.ReadKey();
            #endregion

string转为枚举

 #region//将字符串转为枚举类型
            //string num = "2";
            //Day ss=(Day)Enum.Parse(typeof(Day), num);
            //Console.WriteLine(ss);
            //Console.ReadKey();
            #endregion

枚举转为string

 #region//将枚举类型转为string
            //Day day = Day.mon;
            //string num=day.ToString();
            //Console.WriteLine(num);
            //Console.ReadKey();
            #endregion

小练习

       public enum Day
        {
            mon,
            fri,
            wes,
            thr,
            thu,
            sat,
            sun
        }     
//提示用户选择一个在线状态，我们接受，并将用户的输入转换成枚举类型。
            //再次打印到控制台中
            Console.WriteLine("请输入1到6");
            string num=Console.ReadLine();
            switch (num)
            {
                case "1":Console.WriteLine((Day)Enum.Parse(typeof(Day), num)); 
                    break;
                case "2":Console.WriteLine((Day)Enum.Parse(typeof(Day), num));
                    break;
                case "3":Console.WriteLine((Day)Enum.Parse(typeof(Day), num));
                    break;
                case "4":
                    Console.WriteLine((Day)Enum.Parse(typeof(Day), num));
                    break;
            }
            Console.ReadKey();

---

结构

 public struct Person
        {
            public string _name;
            public int _age;
            public Gender _gender;
        }
         public enum Gender
            {
                boy,
                girl
            }
  Person person;
            person._name = "张三";
            person._age = 1;
            person._gender = Gender.boy;
            Console.WriteLine("姓名：{0}，年龄：{1}，性别：{2}",person._name,person._age,person._gender);
            Console.ReadKey();

---

外加简单数据类型的转换

显式类型转化

即强制类型转换。显式转换需要强制转换运算符，而且强制转换会造成数据丢失

  Console.WriteLine("打印字符串喽1");
            string num1=Console.ReadLine();
            Console.WriteLine("打印字符串喽2");
            string num2=Console.ReadLine();
            Console.WriteLine("打印int喽");
            int num3=int.Parse(Console.ReadLine());
            int a=Convert.ToInt32(num1);
            double b=Convert.ToDouble(num2);
            Console.WriteLine(num3);
            Console.WriteLine(a);
            string c=b.ToString();
            Console.WriteLine(c);
            Console.ReadKey();

隐式类型转换

从小的整数类型转换为大的整数类型

 int a = 10;
            double b=(double)a;
            Console.WriteLine(b);
            Console.ReadKey();