c++ - 错误: “expression must have class type” & “left of must have class/struct/union”

Question

我有一个程序正在使用用户指定的测量值来计算矩形的面积。出于特定原因，我正在使用一个类来执行此操作，但是我的编译器会生成两个错误...

expression must have class type

left of '.getArea' must have class/struct/union

我该如何解决？

Rectangle.h

class Rectangle
{
private:
  int length;
  int width;
  int area = length * width;

public:
  Rectangle(int l, int w);
  int getLength();
  void setLength(int l);
  int getWidth();
  void setWidth(int w);
  int getArea();
  void setArea(int a);
};

Rectangle.cpp

Rectangle::Rectangle(int l, int w)
{
   length = l;
   width = w;
}
--some code--
int Rectangle::getArea()
{
   return area;
}
void Rectangle::setArea(int a)
{
   area = a;
}

Area.cpp

int i, lth, wth;

for (i = 0; i < 3; i++)
{
    cout << "Enter your measurements, length first" << endl;
    cin >> lth >> wth;
    Rectangle rMeasure(int lth, int wth);
    cout << "Area of this rectangle is: " << rMeasure.getArea(); //problem code
}

Answer 1

这个

Rectangle rMeasure(int lth, int wth);

是一个函数声明。

看来你是说

Rectangle rMeasure(lth, wth);