Everything else looks fine but still getting linking errors at the end:
1>Finished searching libraries 1>Finished pass 1 1>Generating non-SAFESEH image. 1>Invoking CVTRES.EXE: 1> /machine:x86 1> /verbose 1> /out:"C:\Users\ocuk\AppData\Local\Temp\lnk9464.tmp" 1> /readonly 1> ".\Debug\Virtual functions.exe.embed.manifest.res" 1>Microsoft (R) Windows Resource To Object Converter Version 9.00.21022.08 1>Copyright (C) Microsoft Corporation. All rights reserved. 1>adding resource. type:MANIFEST, name:1, language:0x0409, flags:0x30, size:2048 1>fig10_10.obj : error LNK2019: unresolved external symbol "public: virtual void __thiscall Circle::print(void)const " (?print@Circle@@UBEXXZ) referenced in function _main 1>fig10_10.obj : error LNK2019: unresolved external symbol "public: virtual void __thiscall Point::print(void)const " (?print@Point@@UBEXXZ) referenced in function _main 1>C:\Users\ocuk\Documents\C++\Chapter 10\Virtual functions\Debug\Virtual functions.exe : fatal error LNK1120: 2 unresolved externals 1>Build log was saved at "file://c:\Users\ocuk\Documents\C++\Chapter 10\Virtual functions\Virtual functions\Debug\BuildLog.htm" 1>Virtual functions - 3 error(s), 0 warning(s) ========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ========== After adding VERBOSE I am getting a new error:
1>------ Rebuild All started: Project: Virtual functions, Configuration: Debug Win32 ------ 1>Deleting intermediate and output files for project 'Virtual functions', configuration 'Debug|Win32' 1>Compiling... 1>circle.cpp 1>fig10_10.cpp 1>point.cpp 1>Generating Code... 1>Compiling manifest to resources... 1>Microsoft (R) Windows (R) Resource Compiler Version 6.0.5724.0 1>Copyright (C) Microsoft Corporation. All rights reserved. 1>Linking... 1>LINK : fatal error LNK1104: cannot open file 'VERBOSE.obj' 1>Build log was saved at "file://c:\Users\ocuk\Documents\C++\Chapter 10\Virtual functions\Virtual functions\Debug\BuildLog.htm" 1>Virtual functions - 1 error(s), 0 warning(s) ========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ========== I'm getting the following errors when I try to build my project. What has happened is that I have written new header files (which are the same as the old ones except one of the functions in now virtual. According to the text I am working from no modifications to the corresponding .cpp files are necessary so I simply copied them from the previous project, by clicking on source files and choosing add existing. I then went to the project properties/"C/C++"/General and added the path where the .cpp files are located, however I am still getting the linking errors shown:
1>------ Build started: Project: Virtual functions, Configuration: Debug Win32 ------ 1>Compiling... 1>circle.cpp 1>point.cpp 1>fig10_10.cpp 1>Generating Code... 1>Linking... 1>fig10_10.obj : error LNK2019: unresolved external symbol "public: virtual void __thiscall Circle::print(void)const " (?print@Circle@@UBEXXZ) referenced in function _main 1>fig10_10.obj : error LNK2019: unresolved external symbol "public: virtual void __thiscall Point::print(void)const " (?print@Point@@UBEXXZ) referenced in function _main 1>C:\Users\ocuk\Documents\C++\Chapter 10\Virtual functions\Debug\Virtual functions.exe : fatal error LNK1120: 2 unresolved externals 1>Build log was saved at "file://c:\Users\ocuk\Documents\C++\Chapter 10\Virtual functions\Virtual functions\Debug\BuildLog.htm" 1>Virtual functions - 3 error(s), 0 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
//Fig 10.9:circle.h //Circle class contains x-y coordinate pair and radius #ifndef CIRCLE_H #define CIRCLE_H #include "point.h" //Point class definition class Circle: public Point{ public: //default constructor Circle(int=0, int=0, double=0.0); void setRadius( double); //set radius double getRadius() const; //return radius double getDiameter() const; //return diameter double getCircumfernce() const; //return circumfernce double getArea() const; //return area virtual void print() const; //output Circle object private: double radius; //Circle's radius }; #endif //Fig. 10.8:point.h //Point class definition represents an x-y coordinate pair #ifndef POINT_H #define POINT_H class Point{ public: Point(int=0, int=0); //default constructor void setX(int); //setX in coordinate pair int getX() const; //return x in coordinate pair void setY(int); //set y in coordinate pair int getY() const; //return y from coordinate pair virtual void print() const; //output Point object private: int x; //x part of coordinate pair int y; //y part of coordinate pair }; #endif //Fig 10.4: circle.cpp // Circle class member-function definitions #include <iostream> using std::cout; #include "circle.h" //Cicle class definition //default constructor Circle::Circle(int xValue, int yValue, double radiusValue):Point (xValue, yValue)//call base class constructor { setRadius(radiusValue); }//end circle constructor //set Radius void Circle::setRadius(double radiusValue) { radius=(radiusValue<0.0?0.0:radiusValue); }//end fuinction setRadius //return radius double Circle::getRadius() const { return radius; }//end finction getRadius //calculate and return diameter double Circle::getDiameter() const { return 2*getRadius(); } //calculate and return diameter double Circle::getCircumference() const { return 3.14159*getDiameter(); } //calculate and return area double Circle::getArea() const { return 3.14159*getRadius()*getRadius(); }//end function getArea //output Circle object void Circle::print() const { cout << "center = "; Point::print(); //invoke Point's print function cout << "; radius = " << getRadius(); }//end function print //Fig. 10.2:point.cpp //Point class member function definitions #include <iostream> using std::cout; #include "point.h" //Point clss deinition //default constructor Point::Point(int xValue, int yValue):x(xValue),y(yValue) { //empty body } //set x in coordinate pair void Point::setX( int xValue) { x=xValue; //no need for validation }//end function setX //return x from coordinate pair int Point::getX() const { return x; }//end function getX //set y in coordinate pair void Point::setY( int yValue) { y=yValue; //no need for validation }//end function setY //return y from coordinate pair int Point::getY() const { return y; }//end function getY //output Point object void Point::print() const { cout << '[' << getX() << ", " << getY() << ']'; } //end function print //Fig. 10.10: fig10_10.cpp //Introducing polymorphism, virtual functions and dynamic binding #include <iostream> using std::cout; using std::endl; using std::fixed; #include <iomanip> using std::setprecision; #include "point.h" //Point class definition #include "circle.h" //Circle class definition int main() { Point point(30,50); Point *pointPtr=0; Circle circle(120,89,2.7); Circle *circlePtr=0; //set floating point precision cout << fixed <<setprecision(2); //output objects point and circle using static binding cout << "Invoking print function on point and circle " << "an objects with static binding " << "ananPoint: "; point.print(); //static binding cout << "anCircle: "; circle.print(); //static binding //output pbjects print and cicrle using dynamic binding cout << "\n\nInvoking print function on point and circle " << "\nobjects with dynamic binding"; //aim base-class pointer at base-class object and print pointPtr=&point; cout << "\n\nCalling virtual function print with base-class" << "\npointer to a base-class object" <<"\ninvokes base-class print function:\n"; pointPtr->print(); //aim derived calss pointer at derived class //object and print circlePtr=&circle; cout << "\n\nCalling virtual function print with " <<"\nderived-class pointer to derived class object " <<"\ninvokes derived class print function:\n"; circlePtr->print(); //aim-base calss pointer at derive class object and print pointPtr=&circle; cout << "\n\nCalling virtual function print with base-class" << "\npointer to derived class object " <<"\ninvokes derived class print function:\n"; pointPtr->print(); //polymorphiosm invokes ciecle's print cout << endl; return 0; } 
