制作日历c++（初学者）

Question

我正在制作日历，并且我已设法显示日历的标题，但我不知道如何使正文或月份的实际日期/数字与每个月对齐以及如何使它们显示。该计划是让用户输入他们想要查看日历的年份。我已经设置了一个函数来获取用户希望的年份，并检查它是否是闰年，并检查该年第一天的日期。 我正在以这种格式制作日历

    #include <iostream>
    #include <iomanip>

    using namespace std;

    

    int GetFirstDay(int year);

    void main()
    {
        int year, numdays;
        int month = 1;
        // getting the user to give the year
        cout << "Enter year: ";
        cin >> year;
        cout << "\n\n";

        // getting first day of given year
        int First_Day = GetFirstDay(year);
        while (month <= 12) {
            switch (month) {
            //Body
            case 1:
                numdays = 31;
                cout << "January" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 2:
                if (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)) { numdays = 29; }
                else { numdays = 28; }
                cout << "Febrary" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 3:
                numdays = 31;
                cout << "March" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 4:
                numdays = 30;
                cout << "April"<< endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 5:
                numdays = 31;
                cout << "May" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 6:
                numdays = 30;
                cout << "June" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 7:
                numdays = 31;
                cout << "July" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 8:
                numdays = 31;
                cout << "August" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 9:
                numdays = 30;
                cout << "September" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 10:
                numdays = 31;
                cout << "October" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 11:
                numdays = 31;
                cout << "November" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;

            case 12:
                numdays = 31;
                cout << "December" << endl;
                cout << "S  M  T  W  T  F  S" << endl;
                cout << "-------------------" << endl << endl;
                break;
            }
            month++;
        }



    }

    int GetFirstDay(int year) {
        int century = (year - 1) / 100;
        int y = (year - 1) % 100;
        int weekday = (((29 - (2 * century) + y + (y / 4) + (century / 4)) % 7) + 7) % 7;
        // 0 would be sunday and 6 would be Saturday
        return weekday;

     }

Answer 1

首先，您需要一个函数来告诉您今天是哪一天，给定日、月和年。

Index    Day 
0        Sunday 
1        Monday 
2        Tuesday 
3        Wednesday 
4        Thursday 
5        Friday 
6        Saturday

找到每个月的开始日期，并相应地打印制表符空格。例如，如果开始日是星期三，则根据您的格式打印 3 个制表符空格或任意数量的空格。每个月都这样做，你就会得到你想要的对齐方式

//A Function that returns the index of the day of the date - day/month/year 
int dayNumber(int day, int month, int year) 
{ 

    static int t[] = { 0, 3, 2, 5, 0, 3, 5, 1, 
                    4, 6, 2, 4 }; 
    year -= month < 3; 
    return ( year + year/4 - year/100 + 
            year/400 + t[month-1] + day) % 7; 
} 

提示：不要对月份进行硬编码，而是使用一个函数或数组将月份名称作为字符串返回，以便您可以循环 12 个月

string getMonthName(int monthNumber) 
{ 
    string months[] = {"January", "February", "March", 
                    "April", "May", "June", 
                    "July", "August", "September", 
                    "October", "November", "December"
                    }; 

    return (months[monthNumber]); 
} 

Answer 2

使用高级文本格式制作带有假期列表的商业风格日历转到https://codingbigdataalgorithm.com/