c#入门遇到小问题一个，大家给我看看啊
刚开始学习c#，照这书上写一个关于类方面的实例，是在vs2005中新建的控制台应用程序项目，代码如下，
using System;
using System.Collections.Generic;
using System.Text;
namespace ConsoleApplication1
{abstract class shape
{ public const double p1=3.14;
protected double x,y
public shape()//构造无参函数
{x=y=0;
}
public shape(double x,double y)
{this.x=x;
this.y=y;
}
public abstract double area }
class rectangle:shape
{public rectangle():base
public rectangle(double x,double y):base(x,y){}
public override void double area()
{return(x*y);}
public double length
{get{return x;}set{if(value> 0){x=value;}}}
public double width
{get{return y;}set{if(value> 0){y=value;}}}
}
class ellipse:shape
{public ellipse(double x,double y):base(x,y){}
public override void double area()
{return pi*x*y;}
}
class circle:ellipse
{public circle (double r):base(r,0){}
public override void double area()
{
return pi*x*x;
}
}
}
class Program
{
static void Main(string[] args)
{
double len = 2.5;
double wid = 3.0;
double rad = 4.1;
rectangle arect=new rectangle();
arect.length=len;
arect.width=wid;
circle acirc=new circle(rad);
Console.WriteLine( "area of rect is:{0} ",arect.area());
Console.WriteLine( "area of circ is:{0} ",acirc.area());
}
}
就是3个派生类的时候，每次重载基类的area的时候，就说那个double不对，为什么呢
我也不知道描述的对不对，大家贴到vs里运行一下就知道我遇到什么问题了，帮帮忙吧
[解决办法]
public override void double area()
void 没有返回值 double返回double型
而且我觉得看这段代码很晕,不整齐
[解决办法]
大哥，你的代码好多错
错误的主要原因是void double area（） ,因为void表示无返回值，double表示返回double，自然就错了
另外的错就不说了
看下面
using System;
using System.Collections.Generic;
using System.Text;
namespace ConsoleApplication1
{
abstract class shape
{
public const double pi = 3.14;
protected double x, y;
public shape()//构造无参函数
{
x = y = 0;
}
public shape(double x, double y)
{
this.x = x;
this.y = y;
}
public abstract double area();
}
class rectangle : shape
{
public rectangle() : base() { }
public rectangle(double x, double y) : base(x, y) { }
public override double area()
{
return (x * y);
}
public double length
{
get
{
return x;
}
set
{
if (value > 0)
{
x = value;
}
}
}
public double width
{
get
{
return y;
}
set
{
if (value > 0)
{
y = value;
}
}
}
}
class ellipse : shape
{
public ellipse(double x, double y) : base(x, y) { }
public override double area()
{
return pi * x * y;
}
}
class circle : ellipse
{
public circle(double r) : base(r, 0) { }
public override double area()
{
return pi * x * x;
}
}
class Program
{
static void Main(string[] args)
{
double len = 2.5;
double wid = 3.0;
double rad = 4.1;
rectangle arect = new rectangle();
arect.length = len;
arect.width = wid;
circle acirc = new circle(rad);
Console.WriteLine( "area of rect is:{0} ", arect.area());
Console.WriteLine( "area of circ is:{0} ", acirc.area());
}
}
}
[解决办法]
似乎你抄代码的时候抄错了好多地方
[解决办法]
恭喜！见者有分！
