c++ - 显示函数的枚举值

Question

想法是根据定义的结构和枚举以表格格式显示从用户那里收集来的所有数据。我已经收到一些有关switch语句使用的警告，但最令人沮丧的事情似乎是在尝试显示值时使用“s.width”。当我尝试编译时，它建议在s.width中的s之前使用分号，并继续将分号移至下一个值。我从枚举中引用值的方式是否有些不正确？

#include <iostream>
#include <string>
#include <iomanip>
using namespace std;

//TODO 1: ShapeKind Enumeration goes here
enum class ShapeKind{
      CIRCLE,SQUARE,RECTANGLE
};

//TODO 2: Shape Structure goes here
struct Shape{
     ShapeKind kind;
     double length, width;
};

// Function prototypes and definitions
double area(Shape s);
//TODO 3: area() definition goes here
double area(Shape s){
  double a;
    switch(s.kind){
      case ShapeKind::CIRCLE:
        return a= (s.length * s.width * 3.14) /4 ;
      case ShapeKind::SQUARE:
        return a = s.length *s.length;
      case ShapeKind::RECTANGLE:
        return a = s.length * s.width;

    }

}

double perimeter(Shape s);
//TODO 4: perimeter() definition goes here

double perimeter(Shape s){
  double p;
  switch(s.kind){
      case ShapeKind::CIRCLE:
        return p= s.length * 3.14;

      case ShapeKind::SQUARE:
        return p = s.length *4;

      case ShapeKind::RECTANGLE:
        return p = 2 *(s.length + s.width);

    }


}

string nameOf(Shape s);
//TODO 5: nameOf() definition goes here
string nameof(Shape s){
  switch(s.kind){
      case ShapeKind::CIRCLE:
        return "Circle";
      case ShapeKind::SQUARE:
        return "Square";
      case ShapeKind::RECTANGLE:
        return "Rectangle";

    }
}

void promptAndReadInputFor(Shape& shape);
//TODO 6: promptAndReadInputFor() definition goes here
void promptAndReadInputFor(Shape& s){
    switch(s.kind){

      case ShapeKind::CIRCLE:
        cout <<"Enter the diameter or a circle: "<< endl;
        cin >> s.length;
        s.width =s.length;

      case ShapeKind::SQUARE:
        cout << "Enter the length of one side: "<< endl;
        cin >>s.length;
        s.width=s.length;

      case ShapeKind::RECTANGLE:
        cout << "Enter the length and width: "<< endl;
        cin >>s.length>>s.width;

          if (s.length == s.width)
            {
              s.kind = ShapeKind::SQUARE; 
            }


    }


};

// The main function
int main() {
  // Shape objects
  Shape circle = { ShapeKind::CIRCLE, 0, 0 };
  //TODO 7: define two more shape objects: a square and and a rectangle
  Shape square= {ShapeKind::SQUARE, 0, 0};
  Shape rectangle ={ShapeKind::RECTANGLE, 0, 0}; 

  //TODO 8: Call the promptAndReadInputFor() function on each of the above three shapes
    promptAndReadInputFor(circle);
    promptAndReadInputFor(square);
    promptAndReadInputFor(rectangle);

  //TODO 9: Print a out a report of these shapes in a table-like format

cout << setw(4) << "Shape" << setw(4) << "Width" << setw(4) << "Height" << setw(4) << "Perimeter"<< setw(4) << "Area"<<endl;    
cout << setw(4) << nameOf(circle) << setw(4) s.width  << setw(4) s.length << setw(4) perimeter(circle)<< setw(4) << area(circle)<< endl;

  return 0;
}

Answer 1

您缺少<<

cout << setw(4) << nameOf(circle) << setw(4)  s.width  << setw(4) s.length
    //                                      ^HERE there should probably be '<<' 
    << setw(4) perimeter(circle)<< setw(4) << area(circle)<< endl;