如果他们无法从 if 和 else if 中得到答案，我该如何返回？ C++答案

【问题标题】：How do I make something return if they fail to get answer something from if and else if? C++如果他们无法从 if 和 else if 中得到答案，我该如何返回？ C++
【发布时间】：2020-07-17 05:45:24
【问题描述】：

在输入中输入数字后。我希望用户输入正确的数据。但是在第一次尝试之后，它立即转到 char 函数。如何在 else 语句中放入一个返回函数来重复输入输入的相同函数？

#include<iostream>

int main()
{
    int num;
    std::cout << "Enter specific age library : ";
    std::cin >> num;
    std::cout << "Entered age library : " << num << "\n\n" << std::endl;



    if (num == 19)
    {
        std::cout << "Jaber : September 18, 2000" << "\n" << "Jayjay : July 18, 2000" << "\n";
    }

    else {
        std::cout << "Sorry, but it looks like the number you've entered contains no data on our library." << "\n" << "\n";

    }


    char name[50];
    std::cout << "Enter your name: " << std::endl;

    std::cin >> name;
    puts(name);
}

【问题讨论】：

标签： if-statement input return

【解决方案1】：

您可以尝试将您的第一个输入部分放在 while 循环中，并且只有在 if 条件匹配时才退出 while 循环。像这样：

while(true){
    int num;
    std::cout << "Enter specific age library : ";
    std::cin >> num;
    std::cout << "Entered age library : " << num << "\n\n" << std::endl;

    if (num == 19){
    std::cout << "Jaber : September 18, 2000" << "\n" << "Jayjay : July 18, 2000" << "\n";
    break;
    }

    else {
        std::cout << "Sorry, but it looks like the number you've entered contains no data on our library." << "\n" << "\n";
    }
}

【讨论】：