C++类构造函数

#include <iostream>

using namespace std;

class line {
   public:
      voID setLength( double len );
      double getLength( voID );
      line();     // This is the constructor
   private:
      double length;
};

// Member functions deFinitions including constructor
line::line(voID) {
   cout << "Object is being created" << endl;
}
voID line::setLength( double len ) {
   length = len;
}
double line::getLength( voID ) {
   return length;
}

// Main function for the program
int main() {
   line line;

   // set line length
   line.setLength(6.0); 
   cout << "Length of line : " << line.getLength() <<endl;

   return 0;
}