Main.cc为什么在这里调用复制构造函数?
#include <iostream>
using namespace std;
#include <vector>
#include "Student.h"
int main()
{
Student matilda("100567899", "Matilda");
Student joe("100234555", "Joe");
Student stanley("100234888", "Stanley");
Student timmy("100234888", "Timmy");
vector<Student*> comp2404;
comp2404.push_back(&matilda);
comp2404.push_back(&joe);
comp2404.push_back(&stanley);
comp2404.push_back(&timmy);
vector<Student> vect2;
vect2.push_back(matilda);
vect2.push_back(timmy);
cout<<"all done"<<endl;
return 0;
}
Student.cc
#include <iostream>
using namespace std;
#include <string>
#include "Student.h"
Student::Student(string nu, string na)
: number(nu), name(na)
{
cout<<"-- Student default ctor "<<name<<endl;
}
Student::Student(const Student& stu)
{
name = stu.name;
number = stu.number;
cout<<"-- Student copy ctor "<<name<<endl;
}
Student::~Student()
{
cout<<"-- Student dtor"<<endl;
}
string Student::getName() const { return name; }
void Student::setName(string n) { name = n; }
ostream& operator<<(ostream& output, Student& stu)
{
output<<"Student: "<<stu.number<<" "<<stu.name<<endl;
return output;
}
输出是:
-- Student default ctor Matilda
-- Student default ctor Joe
-- Student default ctor Stanley
-- Student default ctor Timmy
-- Student copy ctor Matilda
-- Student copy ctor Timmy
-- Student copy ctor Matilda
-- Student dtor
all done
-- Student dtor
-- Student dtor
-- Student dtor
-- Student dtor
-- Student dtor
-- Student dtor
为什么vect2
调用拷贝构造函数?矢量不能存储实际的对象(Matilda和Timmy)?另外,为什么“Matilda”在vect2
中被称为两次?
你所说的“实际对象”呢? – ooga
至于额外的“Matilda”,我建议你检查你的代码中没有多余的一个,重新编译并重新运行。 – ooga
@ooga在代码中,只有两个对象都推到“vect2” – Manuel