c#的基本输入与输出

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp2
{
    class Program
    {
        static void Main(string[] args)
        {
            string s = Console.ReadLine();
            int x = Convert.ToInt32(s);
            s = Console.ReadLine();
            int y = Convert.ToInt32(s);
            int z = x + y;
            Console.WriteLine(z);
            Console.ReadKey();

        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp2
{
    class Rectangle
    {
        double length;
        double width;
        public void Accept()
        {
            //成员变量，先相当于赋值
            length = 4.5;
            width = 3.5;
        }

        public double Getarea()
        {
           //一个double型函数，
            return length * width;
  
        }
        public void Display()
        {
            //起到打印的作用
            Console.WriteLine("length:{0}", length);
            Console.WriteLine("width:{0}", width);
            Console.WriteLine("area:{0}", Getarea());
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            //string s = console.readline();
            //int x = convert.toint32(s);
            //s = console.readline();
            //int y = convert.toint32(s);
            //int z = x + y;
            //console.writeline(z);
            //console.readkey();
            //Ctrl+E,C / Ctrl+K,C: 注释选定内容
            //Ctrl + E,U / Ctrl + K,U: 取消选
            //释内容
            Rectangle r = new Rectangle();
            r.Accept();
            r.Display();
            Console.ReadKey();

        }
    }
}