按照指南，我得到一个c3867错误（二进制'＆lt;＆lt;'：没有找到操作符，它采用'void'类型的右操作数）但我不完全确定为什么或如何我“解决它。
我正在尝试使用Composition通过人员类调用birthday.printDate函数，我昨天确实启动了CPP，所以我为我所犯的错误道歉（类名不开始大写等）
这是我的代码：
的main.cpp
#include <iostream>
#include "birthday.h"
#include "people.h"
using namespace std;
int main() {
birthday birthObj(4, 1, 1998);
people User("User", birthObj);
User.printInfo();
system("pause");
}
people.h
#pragma once
#include <string>
#include "birthday.h"
using namespace std;
class people
{
public:
people(string x, birthday bo);
void printInfo();
private:
string name;
birthday dateOfBirth;
};
people.cpp
#include "people.h"
#include "birthday.h"
#include <iostream>
using namespace std;
people::people(string x, birthday bo)
:name(x), dateOfBirth(bo)
{
}
void people::printInfo() {
cout << name << " was born on " << dateOfBirth.printDate() << endl;
}
birthday.h
#pragma once
class birthday
{
public:
birthday(int d, int m, int y);
void printDate();
private:
int day;
int month;
int year;
};
birthday.cpp
#include <iostream>
#include "birthday.h"
using namespace std;
birthday::birthday(int d, int m, int y){
day = d;
month = m;
year = y;
}
void birthday::printDate() {
cout << day << "/" << month << "/" << year << endl;
}
我尽可能地遵循了给出的建议，但我仍然不明白为什么我不能打电话给printDate。