javascript - 如何使用 node.js 的 readline 模块进行两次连续输入？

Question

我正在创建一个程序，从命令行输入两个数字，然后在 node.js 中显示总和。我正在使用 readline 模块来获取标准输入。下面是我的代码。

const readline = require('readline');

const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});

const r2 = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});

rl.question('Please enter the first number', (answer1) => {
    r2.question('Please enter the second number', (answer2) => {
        var result = (+answer1) + (+answer2);
        console.log(`The sum of above two numbers is ${result}`);
    });
    rl.close();
});

这个程序只显示“请输入第一个数字”，当我输入像 5 这样的数字时，第二次输入也需要 5 并显示答案 10

它根本不问第二个问题。请检查一下并告诉我有什么问题。如果有更好的方法来获取多个输入，请告诉我们。

我是node.js的新手

Answer 1

嵌套代码/回调很难阅读和维护，这是使用 Promise 提出多个问题的更优雅的方式

Node 8+

'use strict'

const readline = require('readline')

const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout
})

const question1 = () => {
  return new Promise((resolve, reject) => {
    rl.question('q1 What do you think of Node.js? ', (answer) => {
      console.log(`Thank you for your valuable feedback: ${answer}`)
      resolve()
    })
  })
}

const question2 = () => {
  return new Promise((resolve, reject) => {
    rl.question('q2 What do you think of Node.js? ', (answer) => {
      console.log(`Thank you for your valuable feedback: ${answer}`)
      resolve()
    })
  })
}

const main = async () => {
  await question1()
  await question2()
  rl.close()
}

main()