C#简单实现

编写一个控制台应用程序，输入三角形或者长方形边长，计算其周长和面积并输出

using System;

 

using System.Collections.Generic;

 

using System.Linq;

 

using System.Text;

 

 

 

namespace C_Lab1

 

{

 

    class Triangle {

 

        double side1 = double.Parse(Console.ReadLine());

 

        double side2 = double.Parse(Console.ReadLine());

 

        double side3 = double.Parse(Console.ReadLine());

 

        public void area()

 

        {

 

            double area;

 

            double Cosc = (side1 * side1 + side2 * side2 - side3 * side3) / (2 * side1 * side2);

 

            area = 0.5*side1*side2*System.Math.Sqrt(1-Cosc*Cosc);

 

            Console.WriteLine("a为{0}", side1);

 

            Console.WriteLine("b为{0}", side2);

 

            Console.WriteLine("c为{0}", side2);

 

            Console.WriteLine("三角形的面积为{0}", area);

 

 

 

        }

 

        public void input() {

 

            Console.WriteLine("请输入三角形的三边长度");

 

          

 

 

 

        }

 

        

 

    }

 

    class rectangle

 

    {

 

        double side1 = double.Parse(Console.ReadLine());

 

        double side2 = double.Parse(Console.ReadLine());

 

        public void area()

 

        {

 

            double area;

 

            area = side1 * side2;

 

            Console.WriteLine("长方形长为{0}", side1);

 

            Console.WriteLine("长方形宽为{0}", side2);

 

            Console.WriteLine("长方形的面积为{0}", area);

 

 

 

        }

 

        public void input()

 

        {

 

            Console.WriteLine("请输入长方形的长和宽");

 

           

 

            

 

 

 

        }

 

 

 

 

 

    }

 

    class Program

 

    {

 

        static void Main(string[] args)

 

        {

 

            

 

            Console.WriteLine("请选择要计算面积的图形 1 三角形 2 长方形");

 

            //choice = Console.Read();

 

            //Console.WriteLine(choice);

 

            int choice = int.Parse(Console.ReadLine());

 

            if (choice == 1) {

 

                Console.WriteLine("请输入三角形的三边长:输入一个数据回车一次");

 

                Triangle tri = new Triangle();

 

                

 

                tri.area();

 

            }

 

            else if (choice == 2)

 

            {

 

                Console.WriteLine("请输入长方形的长和宽:输入一个数据回车一次");

 

                rectangle rec = new rectangle();

 

               

 

                rec.area();

 

            }

 

            

 

           

 

            //Console.WriteLine("Hello World!");//这个一句输出语句！

 

            //Console.ReadKey();//这个语句为了防止输出窗口一跳而过！

 

        }

 

    }

 

}