c++ - 单继承 C++ 和头文件

Question

我得到一个

expected class-name before '{' token

在下面的代码中

saltwaterfish.h 头文件:

#ifndef SALTWATERFISH_H
#define SALTWATERFISH_H


class saltwaterfish: public fish
{
public:
    saltwaterfish();
    float GetUnitPrice();
    float GetWeight();
};

#endif // SALTWATERFISH_H

这是定义头文件的正确方法吗

“咸水鱼是鱼的一个亚类”？

我在 saltwaterfish.cpp 中唯一的东西是

#include "fish.h"
#include "saltwaterfish.h"

fish.cpp 类:

#include "fish.h"
#include <iostream>

#include "freshwaterfish.h"
#include "saltwaterfish.h"

using namespace std;

fish::fish()
{
};

float fish::CalculatePrice()
{
    return GetUnitPrice()*GetWeight();
}

float fish::GetUnitPrice()
{
    return 1.0;
}

float fish::GetWeight()
{
    return 1.0;
}

Answer 1

在saltwaterfish.h中包含fish.h头文件

//saltwaterfish.h
#include"fish.h"
#ifndef SALTWATERFISH_H
#define SALTWATERFISH_H


class saltwaterfish: public fish
{
public:
    saltwaterfish();
    float GetUnitPrice();
    float GetWeight();
};
#endif // SALTWATERFISH_H

编译器看不到 Fish 是一个类，因此出现错误。