Question

class Point
{
  private:
    int X, Y;  
  public:
    static const Point Origin;
    static const Point OneZero;
    static const Point ZeroOne;
};

我如何访问原点？

Answer 1

对于静态，写：

Point::Origin

或更完整的例子：

namespace Someplace {
int fun() {
  return Point::Origin.X;
}
}

虽然在课堂范围内不需要资格Point:: - 您只需撰写Origin。

Answer 2

向您的班级添加访问者（“getters”），如下所示：

class Point
{
  private:
    int X, Y;  
  public:
    static const Point Origin;
    static const Point OneZero;
    static const Point ZeroOne;

    int getX() {return X;}
    int getY() {return Y;}
};

然后您可以像这样访问Point的内容：

int originX = Origin.getX();

或者像这样：

Point myPoint;
int pointX = myPoint.getX();

另外，令人困惑的是Point类中有Point类的静态实例。以下可能更符合您的要求：

class Point
{
  public:
    // Added a constructor that takes two arguments
    Point(int pointX, int pointY) {X = pointX; Y = pointY;}

    int getX() {return X;}
    int getY() {return Y;}
  private:
    int X, Y;  
};

int main()
{
  const Point Origin(0,0);
  const Point OneZero(1,0);
  const Point ZeroOne(0,1);

  int originX = Origin.getX();
};

我如何访问静态类成员？

2 个答案: