Question

我正在使用C ++，这只是一个非常基本的程序，但我仍然遇到错误。

错误消息为：

＆＃39; class secondary＆＃39;没有名为＆＃39; getting＆＃39;的成员。

这是为什么？它适用于我的虚空设置，但不适合获取？我在这里做错了什么？

的main.cpp

#include <iostream>
#include <string>
#include "secondary.h"
using namespace std;

int main(){
    secondary s;
    int scale;
    cout << "On a scale of 1-10, how awesome are you?" << endl;
    cin >> scale;
    cout << endl;

    s.setting(scale);
    cout << s.getting();
    return 0;
}

secondary.h

#ifndef SECONDARY_H
#define SECONDARY_H
#include <string>


class secondary
{
    public:
        void setting(int x);
        string getting();
};

#endif // SECONDARY_H

secondary.cpp

#include "secondary.h"
#include <iostream>
#include <string>
using namespace std;


void secondary::setting(int x){
    factor = x;
}

string secondary::getting(){
    string result;
    if(factor < 3){
        result = "You have a very low self esteem.";
    }elseif(factor > 3){
        if(factor > 7){
            result = "You have a very high self esteem."
        }else{
            result = "You have a medium self esteem."
        }
    }
    return result;
}

private factor;

Answer 1

实际上，再看一遍，这个代码有很多问题（关键点缺少分号，private int定义应该在头文件中，而不是cpp文件9t（私有是自己的部分，见下文）：问题，从我所看到的，s尚未实例化，这样做，操作应该正常工作。

还请注意，当在cpp文件中定义因子时，它是在底部定义的，它应该在任何使用要定义的变量之前实际定义（在头文件中更好地满足常见/传统编码标准））。

请检查此测试代码：

的main.cpp

#include <iostream>
#include <string>
#include "secondary.h"
using namespace std;

int main(){
    secondary s;
    int scale;
    cout << "On a scale of 1-10, how awesome are you?" << endl;
    cin >> scale;
    cout << endl;

    s.setting(scale);
    cout << s.getting();
    return 0;
}

secondary.h

#ifndef SECONDARY_H
#define SECONDARY_H
#include <string>

class secondary
{
public:
    void setting(int x);
    std::string getting();

private: // Note: this is how you do private
    int factor; // This is the definition with type int, missing in original
};

#endif // SECONDARY_H

secondary.cpp

#include "secondary.h"
#include <iostream>
#include <string>
using namespace std;

void secondary::setting(int x){
    factor = x;
}

string secondary::getting(){
    string result;
    if (factor < 3){
        result = "You have a very low self esteem.";
    }else if(factor > 3){
        if (factor > 7){
            result = "You have a very high self esteem.";
        }
        else{
            result = "You have a medium self esteem.";
        }
    }
    return result;
}

C ++错误：类中没有成员？

1 个答案: