1 //Date.cpp
2 #include<iostream>
3 #include<time.h>
4 #include<cmath>
5 #include<cstring>
6 using namespace std;
7 //Date_class
8 class Date
9 {
10 private:
11 int year, month, day;
12 int week; //存放星期
13 void IncDay(); //日期增加一天函数
14 int distance(); //设成私有成员,由公有函数调用,距基准日期的天数,设基准日期为1900-1-1---B
15 int Week() { //计算星期
16 return week;
17 }
18 public:
19 Date(int y = 1900,int m = 1,int d = 1); //构造函数(default)
20 void SetSystemDate(); //取得系统日期
21 void SetDate(int yy,int mm,int dd); //日期设置
22
23 bool IsLeapYear(); //是否闰年
24
25 void print_ymd() const; //年月日输出法
26 void print_mdy() const; //月日年输出法
27
28 void AddDay(int days); //A:增加任意天数
29 bool IsEndofMonth() ; //判断是否到了月末--A
30 int Daysof2Date(Date ymd) ; //B:2个日期之间的天数---区别查表法
31
32 void ShowWeek(ostream &out); //显示星期
33 int operator - (Date ymd); //重载 —运算符
34 friend ostream& operator << (ostream &out, Date& ymd); //输出日期
35 };
36
37 Date::Date(int y,int m,int d){
38 SetDate(y,m,d);
39 }
40
41 void Date::SetSystemDate() //取得系统日期
42 {
43 tm *gm; //tm 是时间(含年月日分秒的结构体)
44 time_t t = time(NULL); //time_t 是长整型,,,t是总秒数;
45 gm = gmtime(&t); //函数返回给定的统一世界时间（通常是格林威治时间），如果系统不支持统一世界时间系统返回NULL
46 year = 1900 + gm->tm_year; //现在的年月日分秒
47 month = gm->tm_mon + 1;
48 day = gm->tm_mday;
49 }
50
51 void Date::SetDate(int yy,int mm,int dd) { //附带合法性检查，错误返回系统当前日期
52 //进行日期合法性检查
53 if (yy >= 1900 && yy <= 9999)
54 year = yy;
55 else {
56 cout << "年设置错误：1900~9999之间!(默认设置成系统当前日期)" << endl;
57 SetSystemDate();
58 return ;
59 }
60 if (mm >= 1 && mm <= 12)
61 month = mm;
62 else {
63 cout << "月设置错误：1900~9999之间!(默认设置成系统当前日期)" << endl;
64 SetSystemDate();
65 return;
66 }
67
68 switch(month)
69 {
70 //小月天数
71 case 4:
72 case 6:
73 case 9:
74 case 11:
75 if (dd >= 1 && dd <= 30)
76 day = dd;
77 else {
78 cout << "日设置错误：1900~9999之间!(默认设置成系统当前日期)" << endl;
79 SetSystemDate();
80 return ;
81 }
82 case 2: //2月
83 if ( (IsLeapYear() && dd >= 1 && dd <= 29) || (!IsLeapYear() && dd >= 1 && dd <= 28) )
84 day = dd;
85 else {
86 cout << "日设置错误：1900~9999之间!(默认设置成系统当前日期)" << endl;
87 SetSystemDate();
88 return ;
89 }
90 default : //大月
91 if (dd >= 1 && dd <= 31)
92 day = dd;
93 else {
94 cout << "年设置错误：1900~9999之间!(默认设置成系统当前日期)" << endl;
95 SetSystemDate();
96 return ;
97 }
98 }
99 }
100
101 bool Date::IsLeapYear()
102 {
103 return (year%4 == 0 && year%100 != 0) || (year%400 == 0);
104 }
105
106 void Date::print_ymd() const //年月日输出法
107 {
108 cout << year << "-" << month << "-" << day;
109 }
110
111 void Date::print_mdy() const
112 {
113 const char *MonthName[12] = {"Jau","Feb","Mar","Apri","May","June","July","Aug","Sept",
114 "Oct","Nov","Dec"};
115 cout << MonthName[month-1] << " " << day << "," << year ;
116 }
117
118 void Date::IncDay() //增加一天
119 {
120 if(IsEndofMonth()) //增加天数，记得要判断是否是年末，月末
121 {
122 if(month == 12)
123 {
124 day = 1; month = 1; year++;
125 }
126 else //已经是IsEndMonth
127 day = 1; month++;
128 }
129 else
130 day++;
131 }
132
133 bool Date::IsEndofMonth()
134 {
135 switch(month)
136 {
137 case 4:
138 case 6:
139 case 9:
140 case 11: return day == 30;
141 case 2:
142 if (IsLeapYear())
143 return day == 29;
144 else
145 return day == 28;
146 default:
147 return day == 31;
148 }
149 }
150 void Date::AddDay(int days)
151 {
152 for (int i = 0; i <= days; i++) //增加多少天--day1->day2 = day+1
153 {
154 IncDay();
155 }
156 }
157
158 /*int years = year - 1; //相隔多少年，，用其算的才是前几年应该有的天数
159 totalDays = years*365 + years/4 - years/100 + years/400 //因为DAY...是按闰年算的年份包含闰年的已经算好
160 + DAYS_BEFORE_MONTH[month-1] + day;
161 if (IsLeapYear() && month > 2) totalDays++;
162 //(闰年)当大于2月时，天数要加1；(注：该法查表代码简洁，但是需要记住表)*/
163
164 int Date::distance() //距离基准日期的天数, 先算到指定年的天数+一月到指定月份天数+指定天数
165 {
166 int days;
167 int years = year-1900;
168 days = years*365 + years/4 - years/100 + years/400; //不计闰年的天数
169 // if(years) //
170 // days += (years-1)/4; //逢闰年+1天
171 switch(month) //此处方法不错，从12月份算起,输入多少月份就能加到哪个月
172 { //注意，无break；
173 case 12: days = days + 30;
174 case 11: days = days + 31;
175 case 10: days = days + 30;
176 case 9: days = days + 31;
177 case 8: days = days + 31;
178 case 7: days = days + 30;
179 case 6: days = days + 31;
180 case 5: days = days + 30;
181 case 4: days = days + 31;
182 case 3:
183 if (IsLeapYear())
184 days = days + 29;
185 else
186 days = days + 28;
187 case 2: days = days + 31;
188 default : break;
189 }
190 days = days + day; //多少天只要加多少天就可以了,(年月已经知道过了多少天)
191 return days;
192 }
193
194 int Date::Daysof2Date(Date ymd) //两个日期的天数
195 {
196 int days;
197 days = abs(distance()-ymd.distance()); //distance()返回值是指定日期到基准类的天数(本类日期-指定日期)
198 return days; //2个日期之间的天数
199 }
200
201 void Date::ShowWeek(ostream &out) //显示该日期是星期几
202 {
203 week = distance() % 7;
204 const char w[7][3] = {"天", "一", "二", "三", "四", "五", "六"};
205 out << year << "-" << month << "-" << day << "--星期" << w[week] << endl;
206 }
207
208 int Date::operator - (Date ymd)
209 {
210 return Daysof2Date(ymd);
211 }
212
213 ostream& operator << (ostream& out, Date& ymd)
214 {
215 ymd.ShowWeek(out);
216 return out;
217 }
218
219 int main(void)
220 {
221 Date date1, date2;
222 int year, month, day;
223 cout << "please input year, month, day: " << endl;
224 cin >> year >> month >> day;
225 // date1.SetDate(2013,1,27);
226 // cout << "the current date is : " << endl;
227 // date1.print_ymd();
228 // date1.print_mdy();
229 // date1.AddDay(100);
230 // cout << "After 100 days , the date is :";
231 // date1.print_ymd();
232 date1.SetDate(year, month, day);
233 cout << date1;
234
235 cout << "please input the date(year,month,day) in the future : " << endl;
236 cin >> year >> month >> day;
237 date2.SetDate(year,month,day);
238 date2.print_mdy();
239 cout << " 距离 :";
240 date1.print_mdy();
241 cout << " have "<< date1-date2 << " days" << endl;
242
243 cout << "输入(想要经历的)天数(将显示当前日期后(N天)的日期: " << endl;
244 cin >> day;
245 date1.print_ymd();
246 date1.AddDay(day);
247 cout << ", After " << day << " days, the date is : " << date1;
248
249 return 0;
250 }
时间： 2024-08-08 09:37:18