c++ - 错误 C2280；执行 employees.erase() 时出现 operator =(const Employee &) 问题

Question

主题(我的意思是重载运算符、默认和复制构造函数等)对我来说是新事物，我真的不得到它。我试图避免它，但它还是捕获了我。我有一个容器 std::vector<Employee>与对象。甚至以为我不使用 = operator

我得到错误: C2280 'Employee &Employee::operator =(const Employee &)': attempting to reference a deleted function .

如果我删除 employees.erase(employees.begin() + 1); 这行，错误就会停止

我发现这是一个常见问题，但我仍然找不到任何解决方案。请看代码:

#include <iostream>
#include <ostream>
#include <string>
#include <vector>

class Employee
{
public:
    std::string name, profession;
    std::string current_task = "NONE";
    int id, age, warrings;

    std::vector<std::string>& tasks;

    Employee::Employee(std::vector<std::string>& tasks) : tasks(tasks)
    {
        warrings = 0;
    };

    virtual void AssignNewTask(std::string input_string)
    {
        for (unsigned int i = 0; i < tasks.size(); i++)
        {
            if (input_string == tasks[i])
            {
                current_task = input_string;
                std::cout << ">> Przydzielony nowy task!" << std::endl;
                return;
            }
        }

        std::cout << input_string << "nie nalezy do listy obowiazkow " << profession << std::endl;
    }
};

class HR : public Employee
{
private:
    static std::vector<std::string> tasks;

public:
    HR::HR() : Employee(tasks)
    {
        Employee::profession = "HR Specialist";
    }
};

class Helpdesk : public Employee
{
private:
    static std::vector<std::string> tasks;

public:
    Helpdesk::Helpdesk() : Employee(tasks)
    {
        Employee::profession = "Helpdesk Technician";
    }
};

std::vector<std::string> HR::tasks = { "HR task" };
std::vector<std::string> Helpdesk::tasks = { "Helpdesk task" };

bool operator==(const Employee & obj, const std::string & std)
{
    if ((obj.name == std) || (std == obj.name))
    {
        return true;
    }
    else
    {
        return false;
    }
}

int main()
{
    std::vector<Employee> employees;
    std::cout << "Welcome message" << std::endl;

    // it works
    employees.push_back(HR());
    employees.push_back(Helpdesk());

    // it also works
    employees.pop_back();
    employees.push_back(Helpdesk());

    // the issue occurs !
    employees.erase(employees.begin() + 1);

    system("pause");
}

我想我应该重载 = operator但我什至不知道如何开始。我已经标记了问题发生的地方。

Answer 1

问题出在这里:

class Employee
{
public:
    std::string name, profession;
    std::string current_task = "NONE";
    int id, age, warrings;

    std::vector<std::string> *tasks; // <=== use a pointer

    Employee(std::vector<std::string>& tasks) : tasks(&tasks)
    {
        warrings = 0;
    };

你不能定义一个 operator= 因为你不能分配一个引用(任务)。去掉引用就万事大吉了(可能慢点，但更安全)