在 Node.js 中接受来自命令行的输入

¥Accept input from the command line in Node.js

如何使 Node.js CLI 程序具有交互性？

¥How to make a Node.js CLI program interactive?

Node.js 从版本 7 开始提供 readline 模块 来执行此操作：从可读流（例如 process.stdin 流）获取输入，在 Node.js 程序执行期间，它是终端输入，一次一行。

¥Node.js since version 7 provides the readline module to perform exactly this: get input from a readable stream such as the process.stdin stream, which during the execution of a Node.js program is the terminal input, one line at a time.

const readline = require('node:readline');

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

rl.question(`What's your name?`, name => {
  console.log(`Hi ${name}!`);
  rl.close();
});

这段代码询问用户的名称，一旦输入文本并且用户按下回车键，我们就会发送问候语。

¥This piece of code asks the user's name, and once the text is entered and the user presses enter, we send a greeting.

question() 方法显示第一个参数（一个问题）并等待用户输入。按下 Enter 后，它会调用回调函数。

¥The question() method shows the first parameter (a question) and waits for the user input. It calls the callback function once enter is pressed.

在此回调函数中，我们关闭 readline 接口。

¥In this callback function, we close the readline interface.

readline 提供了其他几种方法，请在上面链接的软件包文档中查看它们。

¥readline offers several other methods, please check them out on the package documentation linked above.

如果你需要输入密码，最好不要回显密码，而是显示 * 符号。

¥If you need to require a password, it's best not to echo it back, but instead show a * symbol.

最简单的方法是使用 readline-sync 包，它在 API 方面非常相似，并且可以开箱即用。

¥The simplest way is to use the readline-sync package which is very similar in terms of the API and handles this out of the box.

Inquirer.js 包 提供了一个更完整、更抽象的解决方案。

¥A more complete and abstract solution is provided by the Inquirer.js package.

你可以使用 npm install inquirer 安装它，然后你可以像这样复制上述代码：

¥You can install it using npm install inquirer, and then you can replicate the above code like this:

const inquirer = require('inquirer');

const questions = [
  {
    type: 'input',
    name: 'name',
    message: "What's your name?",
  },
];

inquirer.prompt(questions).then(answers => {
  console.log(`Hi ${answers.name}!`);
});

Inquirer.js 可让你执行许多操作，例如询问多项选择、单选按钮、确认等。

¥Inquirer.js lets you do many things like asking multiple choices, having radio buttons, confirmations, and more.

值得了解所有替代方案，尤其是 Node.js 提供的内置替代方案，但如果你计划将 CLI 输入提升到一个新的水平，Inquirer.js 是最佳选择。

¥It's worth knowing all the alternatives, especially the built-in ones provided by Node.js, but if you plan to take CLI input to the next level, Inquirer.js is an optimal choice.