c_cpp C ++ - 类和静态成员的示例

Posted 2021-05-14

#include <iostream>

using namespace std;

class Droid{
  private:
    string name;    
  public:
    static int population;
    Droid(const string &s);
    ~Droid(void);
    void SayHi(void) const;
};

Droid::Droid(const string &s)
{
    name = s;
    cout << "Droid " << name << " generated!" << endl;
    ++Droid::population;
}

Droid::~Droid(void)
{
    cout << "Droid " << name << " destroyed!" << endl;
    --Droid::population;
}

void Droid::SayHi(void) const
{
    cout << "Hello! My name is " << name << endl;
}

int Droid::population = 0;

int main(void)
{
    Droid droid1("r2d2");
    cout << "Population: " << Droid::population << endl;
    droid1.SayHi();
    Droid droid2("PD");
    droid2.SayHi();
    cout << "Population: " << Droid::population << endl;
    return 0;
}