用于类和结构之间交互的 C++ 语法

Question

我正在做 C++ 第一学期的作业，但我只是想不出它的工作语法。我需要使用指针将结构作为参数传递给类函数。我复制的这段代码是我最好的尝试，它可以编译，但在询问名字时会崩溃。当我尝试语法的变化时，我收到有关不完整结构、 undefined variable 的错误(warrior was 或无效运算符。我做错了什么？

#include <iostream>

using namespace std;

class StarWars
{
    public:
        int totalNumber;
        struct data_clone
        {
            int ID, timeCounter;
            string name;
        };
        data_clone *warrior;
        void createClone()
        {
            cout << "How many clone warriors do you want to create in total?" << endl;
            cin >> totalNumber;
        }
        void input(struct data_clone *pointer, int total)
        {

            for(int i = 1; i <= total; i++)
            {
                cout << "For warrior number " << i << ":" << endl;
                cout << "What is the warrior's name?" << endl;
                cin >> pointer[i].name;
                cout << "What is the warrior's ID number?" << endl;
                cin >> pointer[i].ID;
                cout << "What is the warrior's time counter?" << endl;
                cin >> pointer[i].timeCounter;
            }
        }
        void lifeSpan(struct data_clone *pointer, int total)
        {
            for(int i = 1; i <= total; i++)
            {
                cout << "Warrior number " << pointer[i].name << ": " << endl;
                while(pointer[i].timeCounter > 0)
                {
                    cout << "Warrior name: " << pointer[i].name << endl;
                    cout << "Warrior ID number: " << pointer[i].ID << endl;
                    cout << "Warrior time counter: " << pointer[i].timeCounter << endl;
                    cout << "Clone is alive." << endl;
                    pointer[i].timeCounter--;
                }
                cout << "Warrior name: " << pointer[i].name << endl;
                cout << "Warrior ID number: " << pointer[i].ID << endl;
                cout << "Warrior time counter: " << pointer[i].timeCounter << endl;
                cout << "Clone is dead." << endl;
            }
        }


};

int main(void)
{
    StarWars clones;
    clones.createClone();
    clones.input(clones.warrior, clones.totalNumber);
    clones.lifeSpan(clones.warrior, clones.totalNumber);
}

Answer 1

您没有初始化内存勇士指向的内存，因此您正在使用未初始化的内存 - 这总是一件坏事。这里有两件事要记住:

使用指针时，总是先初始化它们后面的内存。更喜欢使用 RAII 概念，如 std::unique_ptr/std::shared_ptr

void DoStuff(Widget* w);

std::unique_ptr<Widget> pw = std::make_unique<Widget>();
DoStuff(w.get());

使用普通变量时，使用解引用/引用运算符获取指向变量的指针。

void DoStuff(Widget* w);

Widget widget;
DoStuff(&w);