C# 类的定义及构造函数的重载

<span style="font-family:FangSong_GB2312;font-size:18px;">
1.类的定义及构造函数的重载


代码如下：</span>

<span style="font-family:FangSong_GB2312;font-size:18px;"> </span><pre name="code" class="csharp">using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace _8_4
{
    class student
    {
        string strname;
        public student(string name)
        {
            strname = name;
            Console.WriteLine("姓名?：" + strname + " 性别： 未知" + " 年龄 ： 未知"); 
        } 
        public student(string name,string sex) 
        {
            strname = name;
            Console.WriteLine("姓名：" + strname + " 性别： " + sex + " 年龄： 未知"); 
        }
        public student(string name, string sex,int age)
        {
            strname = name;
            Console.WriteLine("姓名：" + strname + " 性别： " + sex + " 年龄：" + age);
        } 
        ~student()
        { 
            Console.WriteLine("学生信息" + strname + "输出完毕"); 
        }
    }
    class Program
    {
        static void Main(string[] args) 
        {
            Console.WriteLine("输出学生信息："); 
            student stu1 = new student("二狗子"); 
            student stu2 = new student("翠花","女"); 
            student stu3 = new student("狗剩","男",30);
            Console.ReadLine(); 
        }
    }
}

运行结果：

2.方法的重载

代码如下：

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

namespace p_134
{
    
    class Program
    {
        const double PI = 3.1415926;
        double getgriph(double r)
        {
            
            return 2 * PI * r;
        }
        double getgriph(double width,double length)
        {
            return 2 * (width + length);
        }

        static void Main(string[] args)
        {
            try
            {
                
                Program pro = new Program();
                Console.WriteLine("计算圆的周长：");
                double dec_r = Convert.ToDouble(Console.ReadLine());
                Console.WriteLine("圆的周长为：" + pro.getgriph(dec_r));
                Console.WriteLine("输入矩形的长和宽(以逗号分隔)");
                string rectvalue = Console.ReadLine();
                string[] rectsplit = rectvalue.Split(new char[] { ',' });
                double dec_length = Convert.ToInt32(rectsplit[0]);
                double dec_width = Convert.ToInt32(rectsplit[1]);
                Console.WriteLine("矩形的周长为：   " + pro.getgriph(dec_length, dec_width));
            }
            catch (Exception e) { Console.WriteLine(e.Message); }
            Console.ReadLine();
         }
    }
}
运行结果：

3.定义一个类，描述一个矩形，包含有长、宽两种属性，有一个无参数构造方法,对长宽赋初值为10,8；一个带两个参数方法，对长宽赋值；一个计算面积方法。
编写一个测试类，对以上类进行测试，创建一个长方形，定义其长、宽，输出其面积。
<span style="font-family:FangSong_GB2312;font-size:18px;">using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace 类与对象
{
    class rect
    {
        double rect_length ;
        double rect_width ;
        public double Rect_width
        {
            get { return rect_width; }
            set { rect_width = value; }
        }
       

        public double Rect_length
        {
            get { return rect_length; }
            set { rect_length = value; }
        }
        
        public void rect_shape()
        {
            rect_length = 10;
            rect_width = 8;
        }
        public double getarea()
        {
            return rect_length * rect_width;
        }
        static void Main(string[] args)
        {
            rect shape = new rect();
            shape.rect_shape();
            Console.WriteLine("默认矩形的面积：" + shape.getarea());
            Console.WriteLine( );
            shape.rect_length = 100;
            shape.rect_width = 80;
            Console.WriteLine("矩形的长" + shape.Rect_length);
            Console.WriteLine("矩形的宽" + shape.Rect_width);
            Console.WriteLine("矩形的面积：" + shape.getarea());
            Console.ReadLine();
        }
    }
}</span>

运行结果：