c++ - 将对象传递给 C++ 方法

问题描述

对不起语法，不是母语人士。

所以我有一个任务来创建一个简单的程序，你应该能够创建三个人，输入他们的姓名、国家、职业和电话号码。您应该能够将保存的信息打印为电子表格。

所以我想出了这样一段代码：

#include <iostream>
#include <iomanip>

using namespace std;

class Person {
public:
    string surname;
    string name;
    string country;
    string occupation;
    string phone;

    // Set default value
    Person() {
        surname = "empty";
        name = "empty";
        country = "empty";
        occupation = "empty";
        phone = "empty";
    }

    // SET PERSON'S DATA
    void set_surname(string entered_surname) {
        surname = entered_surname;
    }

    void set_name(string entered_name) {
        name = entered_name;
    }

    void set_country(string entered_country) {
        country = entered_country;
    }

    void set_occupation(string entered_occupation) {
        occupation = entered_occupation;
    }

    void set_phone(string entered_phone) {
        phone = entered_phone;
    }

    // RETURN PERSONS DATA
    string get_surname() {
        return surname;
    }
    string get_name() {
        return name;
    }
    string get_country() {
        return country;
    }
    string get_occupation() {
        return occupation;
    }
    string get_phone() {
        return phone;
    }

};

void create_a_frankenstein(Person person) {
    string entered_data;
    cout << "Please, enter person's surname: \n";
    cin >> entered_data;
    person.set_surname(entered_data);

    cout << "Please, enter person's name: \n";
    cin >> entered_data;
    person.set_name(entered_data);

    cout << "Please, enter person's country: \n";
    cin >> entered_data;
    person.set_country(entered_data);

    cout << "Please, enter person's occupation: \n";
    cin >> entered_data;
    person.set_occupation(entered_data);

    cout << "Please, enter person's phone: \n";
    cin >> entered_data;
    person.set_phone(entered_data);
}

int main() {

    Person fst;
    Person snd;
    Person trd;
    Person group[3] = {fst, snd, trd};

    int people_created = 0;

    bool switch_on = true;

    while (switch_on) {
        cout << "What operation would you like to perform: \n";
        cout << "    1) Create new person \n";
        cout << "    2) Print out all of the available information \n";
        cout << "    3) Quit \n";


        //Get the number of operation to perform
        int operation;
        cout << "Please, enter a number: \n";
        cin >> operation;

        switch (operation) {
        //Option 1: create a person
        case 1:
            if (people_created == 3) {
                cout << "It is not possible to create more that three people";
            }

        else {
                create_a_frankenstein(group[people_created]);
                people_created++;
            }
            break;

        //Option 2: print out all of the available information
        case 2:
            for (int i = 0; i < 3; i++) cout << setw(20) << setfill(' ') << left << group[i].get_surname();
            for (int i = 0; i < 3; i++) cout << setw(20) << setfill(' ') << left << group[i].get_name();
            for (int i = 0; i < 3; i++) cout << setw(20) << setfill(' ') << left << group[i].get_country();
            for (int i = 0; i < 3; i++) cout << setw(20) << setfill(' ') << left << group[i].get_occupation();
            for (int i = 0; i < 3; i++) cout << setw(20) << setfill(' ') << left << group[i].get_phone();
            break;

        // Option 3: quit
        case 3:
            switch_on = false;
            break;
        }
    }

}

一切似乎都很好。除了它不会改变对象变量中的信息。

我的猜测是，当我将 Person 类型的对象传递给 create_a_frankenstein() 时，方法会创建对象的副本并开始使用副本而不更改原始对象中的任何内容。

我试过使用指针。我设法在更简单的例子中做我想做的事情：

void first(int* a){
    for (int i = 0; i < 7; i++) {
        a[i] = a[i]+1;
    }
}

int main() {
    int a[7] = {0, 1, 2, 3, 4, 5, 6};
    for (int i=0; i<7; i++) {
        cout << a[i] << ' ';
    }
}

但是当我尝试在实验室中使用它时，它并不那么容易工作。

很高兴收到有关如何解决问题以及我应该复习或深入研究哪些主题的任何建议。在此先感谢您！

标签： c++

c++ - 将对象传递给 C++ 方法

问题描述

解决方案

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