c++ - 如何在函数内部使用 cin？

Question

我是 C++ 的新手，正在尝试制作一个简单的基于文本的游戏。下面的代码应该是欢迎用户加入游戏并询问用户是否要开始游戏。我没有收到任何构建错误，但是当我运行它时，它显示的只是一个空白屏幕。我究竟做错了什么？

代码如下:

string D1(string Original)
{
    cin >> Original;
    return Original;
}

int main ()
{
    string Decision1;
    cout << "Welcome to [game name]" << endl;
    cout << "Would you like to start the game?" << endl;
    cout << "Yes/No" << endl;
    string D1(Decision1);
    system("cls");
    if (Decision1 == "Yes")
    {
        cout << "this happens" << endl;
    }
    else if (Decision1 == "No")
    {
        cout << "that happens" << endl;
    }
}

Answer 1

您必须调用 D1，而不是创建一个名为 D1 的新变量:

std::string D1()
{
    std::string Original;
    std::cin >> Original;
    return Original;
}

int main ()
{
    std::cout << "Welcome to [game name]" << std::endl;
    std::cout << "Would you like to start the game?" << std::endl;
    std::cout << "Yes/No" << std::endl;
    auto Decision1 = D1();
    system("cls");
    if (Decision1 == "Yes")
    {
        std::cout << "this happens" << std::endl;
    }
    else if (Decision1 == "No")
    {
        std::cout << "that happens" << std::endl;
    }
}