类和对象:数据成员之使用默认参数初始化
当创建对象不给定参数时,去掉括号, 如:Date date0;
#include <iostream> using namespace std; class Date { int day, month, year; public: Date(int yy = 1949, int mm = 0, int dd = 0); void myprint(); }; Date::Date(int yy, int mm, int dd):year(yy),month(mm),day(dd){} void Date::myprint() { cout<<year<<"-"<<month<<"-"<<day<<endl; } int main() { Date date0, date1(2015), date2(2015,3), date3(2015,3,26); //当创建对象不给定参数时,去掉括号,如:Date date0; cout<<"date0: "; date0.myprint(); cout<<"date1: "; date1.myprint(); cout<<"date2: "; date2.myprint(); cout<<"date3: "; date3.myprint(); return 0; }