我正在尝试执行以下程序并获得以下错误。请告诉我我错在哪里。 ＆＃34; main.cpp（289）：错误C2535：＆＃39; void __thiscall Line :: setdefaultvalues（void）＆＃39; ：成员函数已经定义或声明＆＃34;
#include<iostream>
#define PI 3.14
#include<conio.h>
using namespace std;
class Point
{
int x;
int y;
public:
Point(int=0,int=0);
int getX();
int getY();
void setX(int);
void setY(int);
};
Point::Point(int ax,int ay){
x = ax;
y = ay;
}
int Point::getX(){
return x;
}
int Point::getY(){
return y;
}
void Point::setX(int ax){
x = ax;
}
void Point::setY( int ay){
y =ay;
}
class Shape
{
public:
virtual void draw()
{
cout<<"draw a shape"<<endl;
}
virtual int calcarea()
{
cout<<"area of shape is"<<endl;
return 0;
}
};
class Rectangle:public Shape
{
Point p1;
Point p2;
Point p3;
Point p4;
public:
Rectangle(Point &a ,Point &b ,Point &c ,Point &d);
Point getp1();
Point getp2();
Point getp3();
Point getp4();
virtual void draw();
virtual int calcarea();
int getlength();
int getWidth();
void show()
{
cout<<"P1 ( "<<p1.getX()<<","<<p1.getY()<<" )"<<endl;
cout<<"P2 ( "<<p2.getX()<<","<<p2.getY()<<" )"<<endl;
cout<<"P3( "<<p3.getX()<<","<<p3.getY()<<" )"<<endl;
cout<<"P4( "<<p4.getX()<<","<<p4.getY()<<" )"<<endl;
//p3.setX(8);
// p3.setY(4);
//p4.setX(0);
//p4.setY(4);
}
void defaultvalues (){
p1.setX(0);
p1.setY(0);
p2.setX(8);
p2.setY(0);
p3.setX(8);
p3.setY(4);
p4.setX(0);
p4.setY(4);
}
};
Rectangle::Rectangle(Point &a,Point &b,Point &c,Point &d){
if ((a.getX()<0||a.getX()>20)||(a.getY()<0||a.getY()>20)||
(b.getX()<0||b.getX()>20) ||(b.getY()<0||b.getY()>20)||
( c.getX()<0||c.getX()>20) ||(c.getY()<0||c.getY()>20)||
(d.getX()<0||d.getX()>20) ||(d.getY()<0||d.getY()>20))
{
std::cout << "Incorect Point value for constructor replacing with default values" <<std::endl;
defaultvalues();
}
else
{
p1.setX(a.getX());
p1.setY(a.getY());
p2.setX(b.getX());
p2.setY(b.getY());
p3.setX(c.getX());
p3.setY(c.getY());
p4.setX(d.getX());
p4.setY(d.getY());
}
/* if( a.getX() != c.getX() )
cout<<"error:a and c must have same x values"<<endl;
if( b.getX() != d.getX() )
cout<<"error:b and c must have same x values"<<endl;
*/
}
int Rectangle ::getlength(){
int l;
if(p1.getX()==p2.getX())
{
l=p2.getY()-p1.getY();
}
else if(p2.getX()==p3.getX())
{
l=p3.getY()-p1.getY();
}
else if(p1.getX()==p4.getX())
{
l=p4.getY()-p1.getY();
}
else
{
l=0.0;
}
int w;
if(p1.getY()==p2.getY())
{
w=p2.getX()-p1.getX();
}
else if(p2.getY()==p3.getY())
{
w=p3.getX()-p1.getX();
}
else if(p1.getY()==p4.getY())
{
w=p4.getX()-p1.getX();
}
else
{
w=0.0;
}
if (l>w)
{
return l;
}
else
{
return w;
}
};
int Rectangle::getWidth()
{
int l;
int w;
if(p1.getX()==p2.getX())
{
l=p2.getY()-p1.getY();
}
else if(p2.getX()==p3.getX())
{
l=p3.getY()-p1.getY();
}
else if(p1.getX()==p4.getX())
{
l=p4.getY()-p1.getY();
}
else
{
l=0.0;
}
if(p1.getY()==p2.getY())
{
w=p2.getX()-p1.getX();
}
else if(p2.getY()==p3.getY())
{
w=p3.getX()-p1.getX();
}
else if(p1.getY()==p4.getY())
{
w=p4.getX()-p1.getX();
}
else
{
w=0.0;
}
if (l<w)
{
return l;
}
else
{
return w;
}
}
int Rectangle::calcarea()
{
int l=getlength();
int w=getWidth();
return l*w;
}
void Rectangle:: draw()
{
cout<<"this is a rectangle"<<endl;
}
class Line : public Shape {
Point p1;
Point p2;
public:
void setdefaultvalues();
Line(Point&a,Point&b)
{
if((a.getX()<0||a.getX()>20)
||(a.getY()<0||a.getY()>20)
||(b.getX()<0||b.getX()>20)
||(b.getY()<0||b.getY()>20))
{
setdefaultvalues();
}
else
{
if((a.getX()==b.getX()||a.getY()==b.getY()))
{
setdefaultvalues();
}
else
{
p1.setX(a.getX());
p1.setY(a.getY());
p2.setX(b.getX());
p2.setY(b.getY());
}
}
}
void setdefaultvalues()
{
p1.setX(0);
p1.setY(0);
p2.setX(8);
p2.setY(8);
}
virtual void draw()
{
cout<<"this is a line"<<endl;
}
void show()
{
cout<<"P1 ( "<<p1.getX()<<","<<p1.getY()<<" )"<<endl;
cout<<"P2 ( "<<p2.getX()<<","<<p2.getY()<<" )"<<endl;
}
};
/*class Circle : public Shape {
Point centre;
double radius;
public:
Circle(Point&a, double r)
{
if(r>0&&r<20)
{
radius=r;
centre.setX(a.getX());
centre.setY(a.getY());
}
else
{
radius=3;
centre.setX(0);
centre.setY(0);
}
}
virtual void draw()
{
cout<<"this is a circle"<<endl;
}
virtual int calcarea()
{
cout<<PI*radius*radius<<endl;
}
};*/
class Triangle:public Shape{
Point p1;
Point p2;
Point p3;
public:
Triangle(Point&a,Point&b,Point&c){
if((a.getX()==b.getX())&&(a.getY()==b.getY())
&&(a.getX()==c.getX())&&(a.getY()==c.getY())
&&(b.getX()==c.getX())&&(b.getY()==c.getY()))
{
std::cout << "Incorect values" <<std::endl;
}
else
{ p1.setX(15);
p1.setY(15);
p2.setX(23);
p2.setY(30);
p3.setX(50);
p3.setY(25);
}
virtual int calcarea();
virtual void draw();
}
virtual int calcarea()
{ int area;
area=[p1*getX()(p2*getY()-p3*getY())+p2*getX()(p3*getY()-p1*getY())+p3*getX()(p1*getY()-p2*getY())]/2;
return area;
}
};
void drawshapes();
int main() {
Point p1(0,0),p2(0,4),p3(4,0),p4(4,4);
Shape* _shape[ 4 ];
_shape[0]=new Rectangle(p1,p2,p3,p4);
/*drawshapes(_shape,4);
calarea(_shape,4);
*/
Line l1(p1,p2),l2(p1,p3);
//_shape[0]=new circle(p1,3);
_shape[1]=new Line(p1,p4);
_shape[2]=new Line(p2,p3);
/* drawshapes(_s,4);
calcarea(_s,4);*/
return 0;
}
答案 0 :(得分：4)
您有以下代码：
class Line : public Shape
{
Point p1;
Point p2;
public:
void setdefaultvalues();
...
void setdefaultvalues()
{
p1.setX(0);
p1.setY(0);
p2.setX(8);
p2.setY(8);
}
...
}
将该代码转换为：
class Line : public Shape
{
Point p1;
Point p2;
public:
void setdefaultvalues()
{
p1.setX(0);
p1.setY(0);
p2.setX(8);
p2.setY(8);
}
...
}
换句话说，取 setdefaultvalues 函数的两个声明并将其减少为一个。
编辑：将定义更改为声明。