Question

这是我的Calendar.cpp文件。

#include <iostream>
#include <string>
#include <sstream>
#include "Calendar.h"

char months[12][10] = { "January", "February", "March","April","May","June","July","August","September","October","November","December" };

问题是在类声明中显示出来。

class Date {

private:
int dd, mm, yy;
public:

Date() {
    dd = 1; mm = 1; yy = 1900;
}

Date(int m, int d, int y) {

    dd = d; mm = m; yy = y;
    bool check = checkdate();
    if (!check) {
        cout << "Invalid date give. Resetting to default" << endl;
        dd = mm = 1; yy = 1900;
    }
}

bool checkdate() {
    bool leap = checkleapyear();
    if (mm>12 || mm <= 0) //check months
        return false;

    if ((mm == 1 || mm == 3 || mm == 5 || mm == 7 || mm == 8 || mm == 10 || mm == 12) && dd>31)
        return false;
    else if (leap && mm == 2 && dd>29)
        return false;
    else if (mm == 2 && dd>28)
        return false;
    else if (dd>30)
        return false;
    return true;
}

bool checkleapyear() {
    if ((yy % 400 == 0) || (yy % 4 == 0 && yy % 100 != 0))
        return true;
    else
        return false;
}
string toString() {
    stringstream ss;
    ss << months[mm - 1] << " " << dd << "," << yy;
    return ss.str();
}
Date nextDate() {
    int y, d, m;

    if (mm == 2) {
        bool flag = checkleapyear();
        if (flag) {
            if (dd >= 29) {
                d = 1;
                m = 3;
            }
            else
                d++;
        }
        else {
            if (dd >= 28) { d = 1; m = 3; }
            else
                d++;
        }
        y = yy;
        return Date(m, d, y);
    }

    if ((mm == 1 || mm == 3 || mm == 5 || mm == 7 || mm == 8 || mm == 10) && dd>31)
    {
        m++;
        d = 1;
        y = yy;
    }
    else if (mm == 12) { m = 1; y = yy++; d = 1; }
    else if (dd>30) {
        m++;
        d = 1;
        y = yy;
    }
    else {
        d = dd + 1;
        m = mm;
        y = yy;
    }

    return Date(m, d, y);

}

void compareDates(Date &d)
{
    if (d.yy>this->yy)
        cout << "The first date comes before the second date" << endl;
    else if (d.yy<this->yy)
        cout << "The second date comes before the first date" << endl;
    else if (d.yy == this->yy) {
        if (d.mm>this->mm)
            cout << "The first date comes before the second date" << endl;
        else if (d.mm<this->mm)
            cout << "The second date comes before the first date" << endl;
        else {

            if (d.dd>this->dd)
                cout << "The first date comes before the second date" << endl;
            else if (d.dd<this->dd)
                cout << "The second date comes before the first date" << endl;
            else {
                cout << "The two dates are equal" << endl;
            }
        }

    }
}

};

这是我的Calendar.h文件。

#ifndef CALENDAR_H
#define CALENDAR_H
#include <iostream>
#include <string>
using namespace std;

class Date {
private:
    int dd, mm, yy;
public:
    Date();
    Date(int m, int d, int y);
    bool checkdate();
    bool checkleapyear();
    string toString();
    Date nextDate();
    void compareDates(Date &d);
};
#endif

我的Calendar.cpp文件中出现错误 - '“Date”：'class'type redefinition“。我试图改变类中的一些东西以使其工作但似乎还有一些其他问题。

Answer 1

由于您已在Calender.h文件中声明了您的类，因此您在Calender.cpp中的实现实际上是在重新定义您的类。正确的方法是使用范围解析运算符' :: '

引用该类

您的Calender.cpp文件应如下所示：

#include <iostream>
#include <string>
#include <sstream>
#include "Calendar.h"

char months[12][10] = { "January", "February", "March","April","May","June","July","August","September","October","November","December" };

// your default no-args class constructor
Date::Date(){
    dd = 1; mm = 1; yy = 1900;
}

/*
        Another Way you could implement your constructor is by using initialisation lists (check our the second link in my answer to know more)
        Date::Date(int m, int d, int y) : mm(m), dd(d), yy(y) { }
*/

Date::Date(int m, int d, int y) {
    // your constructor code here
}

bool Date::checkdate(){
    // your implementation here
}
bool Date::checkleapyear(){
    // your implementation here
}
string Date::toString(){
    // your implementation here
}
Date Date::nextDate(){
    // your implementation here
}
void Date::compareDates(Date &d){
    // your implementation here
}

就是这样。它确实有助于将您的类声明和实现分开。

请查看以下链接，以帮助您更好地理解：

http://www.learncpp.com/cpp-tutorial/89-class-code-and-header-files/

http://www.cppforschool.com/tutorial/separate-header-and-implementation-files.html

'Date'：'class'类型重定义：ERROR（calendar.cpp文件错误）

1 个答案: