9.51 设计一类,它又三个unsigned成员,分别表示年月日。为其编写构造函数,接受一个表示日期的string参数。
程序如下:
#include<iostream> #include<string> using namespace std; class My_Date { public: My_Date(const string &s); unsigned year; unsigned month; unsigned day; }; My_Date::My_Date(const string &s) { unsigned format=0; if(s.find_first_of("/")!=string::npos) format=0x10; if(s.find_first_of(",")!=string::npos) format=0x01; switch(format) { case 0x10: day=stoi(s.substr(0,s.find_first_of("/"))); month=stoi(s.substr(s.find_first_of("/")+1,s.find_last_of("/")-s.find_first_of("/"))); year=stoi(s.substr(s.find_last_of("/")+1,4)); break; case 0x01: day=stoi(s.substr(s.find_first_of("0123456789"),s.find_first_of(",")-s.find_first_of("0123456789"))); if(s.find("Jan")<s.size()) month=1; if(s.find("Feb")<s.size()) month=2; if(s.find("Mar")<s.size()) month=3; if(s.find("Apr")<s.size()) month=4; if(s.find("May")<s.size()) month=5; if(s.find("Jun")<s.size()) month=6; if(s.find("Jul")<s.size()) month=7; if(s.find("Aug")<s.size()) month=8; if(s.find("Sep")<s.size()) month=9; if(s.find("Oct")<s.size()) month=10; if(s.find("Nov")<s.size()) month=11; if(s.find("Dec")<s.size()) month=12; year=stoi(s.substr(s.find_last_of(",")+1,4)); break; } } int main() { My_Date d("99/21/1234"); cout<<d.day<<" "<<d.month<<" "<<d.year<<endl; return 0; }
运行结果如下:
stoi的例子
时间: 2024-08-28 22:09:51