C#函数的重载

◆函数名必须相同方能构成函数重载;

◆函数返回值类型:可以相同,也可以不同(注意:函数的返回类型不足以区分两个重载函数);

◆函数参数类型:必须不同;

◆函数参数个数:可以相同,可以不同

◆函数参数顺序:可以相同,可以不同;

using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace ConsoleApplication{    class Circle    {               private const float PI = 3.141526F;        //1.没有任何已知条件        public static double Area()        {             Console.WriteLine("空空如也！");            return 0;                }        //2.已知圆心坐标        public static double Area(int x1, int y1)        {            Console.WriteLine("这是一个圆点，坐标为({0},{1})",x1,y1);            return 0;        }        //3.已知半径        public static double Area(double r)        {            double theArea;            theArea = PI * r * r;            return theArea;        }        //4.已知圆心坐标和半径        public static double Area(int x1, int y1, double r)        {            Console.WriteLine("这是一个圆点在({0},{1})半径为{2}的圆", x1, y1, r);            return Area(r);                }        //5.已知圆心和圆周边上的一点        public static double Area(int x1, int y1, int x2, int y2)        {            int x = x2 - x1;            int y = y2 - y2;            double r = (double)Math.Sqrt(x*x+y*y);            Console.WriteLine("这是一个圆心在({0},{1}),圆周边一点在({2},{3})的圆，圆的半径为{4}",x1,y1,x2,y2,r);            return Area(r);                }        static void Main(string[] args)        {            int x1=2,x2=4;          //x坐标            int y1=3,y2=5;          //y坐标            double radius=3;        //半径            double CircleArea = 0;            CircleArea = Area();            Console.WriteLine("-->1.面积为{0}",CircleArea);            Console.WriteLine();            CircleArea = Area(x1,y1);            Console.WriteLine("-->2.面积为{0}", CircleArea);            Console.WriteLine();            CircleArea = Area(radius);            Console.WriteLine("-->3.面积为{0}", CircleArea);            Console.WriteLine();            CircleArea = Area(x1, y1, radius);            Console.WriteLine("-->4.面积为{0}", CircleArea);            Console.WriteLine();            CircleArea = Area(x1, y1, x2, y2);            Console.WriteLine("-->5.面积为{0}", CircleArea);            Console.WriteLine();            Console.ReadKey();        }           }}