好的，所以我有一个名为employee的父类和3个子类叫做manager，研究员和工程师。我做了一个矢量，想要列出它们。这就是我如何处理制作。
vector <Employee*,Manager*> EmployeeDB;
Employee *temp;
temp = new Manager(first, last, salary, meetings, vacations);
EmployeeDB.push_back(temp);
我在制作矢量时没有问题，我关心的是列出信息。所有3个子类都有firstname，lastname和salary，但它们的不同之处在于它们具有唯一的不同数据成员，例如Manager具有{{1} } int和vacation的{{1}}值Engineer依此类推。
Employee.h ：
intEmployee.cpp ：
experience主要：
#include <iostream>
#include <string>
using namespace std;
#ifndef EMPLOYEE_h
#define EMPLOYEE_h
class Employee
{
public:
Employee();
Employee(string firstname, string lastname, int salary);
string getFname();
string getLname();
int getSalary();
virtual void getInfo();
private:
string mFirstName;
string mLastName;
int mSalary;
};
#endif
我在#include "Employee.h"
#include <iostream>
#include <string>
using namespace std;
Employee::Employee()
{
mFirstName = "";
mLastName = "";
mSalary = 0;
}
Employee::Employee(string firstname, string lastname, int salary)
{
mFirstName = firstname;
mLastName = lastname;
mSalary = salary;
}
string Employee::getFname()
{
return mFirstName;
}
string Employee::getLname()
{
return mLastName;
}
int Employee::getSalary()
{
return mSalary;
}
void Employee::getInfo()
{
cout << "Employee First Name: " << mFirstName << endl;
cout << "Employee Last Name: " << mLastName << endl;
cout << "Employee Salary: " << mSalary << endl;
}
函数上收到错误。
它说没有#include <vector>
#include <iostream>
#include <string>
#include "Employee.h"
#include "Engineer.h"
#include "Manager.h"
#include "Researcher.h"
using namespace std;
vector <Employee*> EmployeeDB;
Employee *temp;
void add()
{
int emp, salary, vacations, meetings, exp, c;
string first, last, type, school, topic;
bool skills;
do
{
system("cls");
cout << "===========================================" << endl;
cout << " Add Employee " << endl;
cout << "===========================================" << endl;
cout << "[1] Manager." << endl;
cout << "[2] Engineer." << endl;
cout << "[3] Researcher." << endl;
cout << "Input choice: ";
cin >> emp;
system("cls");
} while (emp <= 0 || emp > 3);
cout << "===========================================" << endl;
cout << " Employee Info " << endl;
cout << "===========================================" << endl;
cout << "Employee First name: ";
cin >> first;
cout << "Employee Last name: ";
cin >> last;
cout << "Employee Salary: ";
cin >> salary;
switch (emp)
{
case 1:
cout << "Employee numbers of meetings: ";
cin >> meetings;
cout << "Employee numbers of vacations: ";
cin >> vacations;
temp = new Manager(first, last, salary, meetings,vacations);
EmployeeDB.push_back(temp);
delete temp;
break;
case 2:
cout << endl;
cout << "[1]YES [2]NO" << endl;
cout << "Employee C++ Skills: ";
cin >> c;
if (c == 1)
{
skills = true;
}
else
{
skills = false;
}
cout << "Employee Years of exp: ";
cin >> exp;
cout << "(e.g., Mechanical, Electric, Software.)" << endl;
cout << "Employee Engineer type: ";
cin >> type;
temp = new Engineer(first, last, salary, skills, exp, type);
EmployeeDB.push_back(temp);
delete temp;
break;
case 3:
cout << "Employee School where he/she got his/her PhD: ";
cin >> school;
cout << "Employee Thesis Topic: ";
cin >> topic;
temp = new Researcher(first, last, salary, school, topic);
EmployeeDB.push_back(temp);
delete temp;
break;
}
}
void del()
{
}
void view()
{
for (int x = 0; x < (EmployeeDB.size()); x++)
{
cout << EmployeeDB[x]->getInfo();
}
}
void startup()
{
cout << "===========================================" << endl;
cout << " Employee Database " << endl;
cout << "===========================================" << endl;
cout << "[1] Add Employee." << endl;
cout << "[2] Delete Employee." << endl;
cout << "[3] List Employees." << endl;
cout << "[4] Exit." << endl;
cout << "Please Enter Your Choice: ";
}
int main(int argc, char** argv)
{
bool flag = true;
int choice;
do {
do
{
system("cls");
system("pause>nul");
startup();
cin >> choice;
} while (choice < 0 || choice >4);
switch (choice)
{
case 1:
add();
break;
case 2:
del();
break;
case 3:
view();
break;
case 4:
flag = false;
system("EXIT");
break;
}
} while (flag == true);
return 0;
system("pause>nul");
}
匹配这些操作数
binary'＆lt;＆lt;'：找不到带有void等类型右手操作数的运算符。
答案 0 :(得分：1)
问题是getInfo的返回类型为void，并且您尝试将该返回值放入cout。
了解代码std::cout << val实际调用函数operator<<(ostream& out, const objectType& val)非常重要，其中objectType是＆＃39; val＆＃39;的类型。
在你的情况下，类型是无效的，并且根本没有operator<<的实现将void作为一个类型。因此错误＆＃34;没有找到哪个操作符采用了类型为void的右手操作数...＆＃34;。
为了解决您的问题，您有以下几种选择：
将view()更改为
for (...)
{
EmployeeDB[x]->getInfo();
}
更改getInfo()以返回字符串您想要的信息：
std::string getInfo()
{
std::string info;
info =...
return info;
}
为员工创建operator<<并更改视图以将其调用：
view()
{
for (...)
{
std::cout << EmployeeDB[x];
}
}