Object references are passed in rather than pointers. - C++ Data Type

C++ examples for Data Type:Reference

  1. HOME
  2. C++
  3. Data Type
  4. Reference

Description

Object references are passed in rather than pointers.

Demo Code

                                                
#include <iostream> 
                                                   
class SimpleCat /*w w  w .  ja  va  2s .  c o m*/
{ 
public: 
    SimpleCat(); 
    SimpleCat(SimpleCat&); 
    ~SimpleCat(); 
                                                   
    int GetAge() const { return itsAge; } 
    void SetAge(int age) { itsAge = age; } 
                                                   
private: 
    int itsAge; 
}; 
                                                   
SimpleCat::SimpleCat() 
{ 
    std::cout << "Simple Cat Constructor ..." << std::endl; 
    itsAge = 1; 
} 
                                                   
SimpleCat::SimpleCat(SimpleCat&) 
{ 
    std::cout << "Simple Cat Copy Constructor ..." << std::endl; 
} 
                                                   
SimpleCat::~SimpleCat() 
{ 
    std::cout << "Simple Cat Destructor ..." << std::endl; 
} 
                                                   
const SimpleCat & FunctionTwo (const SimpleCat & theCat); 
                                                   
int main() 
{ 
    std::cout << "Making a cat ..." << std::endl; 
    SimpleCat Frisky; 
    std::cout << "Frisky is " << Frisky.GetAge() << " years old" << std::endl; 
                                                   
    int age = 5; 
    Frisky.SetAge(age); 
    std::cout << "Frisky is " << Frisky.GetAge() << " years old" << std::endl; 
                                                   
    std::cout << "Calling FunctionTwo..." << std::endl; 
    FunctionTwo(Frisky); 
    std::cout << "Frisky is " << Frisky.GetAge() << " years old" << std::endl; 
    return 0; 
} 
                                                    
// functionTwo passes a ref to a const object 
const SimpleCat & FunctionTwo (const SimpleCat & theCat) 
{ 
    std::cout << "Function Two. Returning..." << std::endl; 
    std::cout << "Frisky is now " << theCat.GetAge() << " years old" << std::endl; 
    // theCat.SetAge(8);   const! 
    return theCat; 
}

Result


Related Tutorials