NodeJS"readline"模块不输出提示 [英] NodeJS "readline" module not outputting prompt

问题描述

使用NodeJS，我试图制作一个笔记"管理器只是为了好玩，但是当我尝试使用readline.question()获得用户对他们想做的事情的输入(即创建一个新的笔记，删除记事)，则不会显示提示.关于如何解决此问题有什么建议吗?

Using NodeJS, I was trying to make a 'note' manager just for fun, but when I tried to use readline.question() to get the user's input on what they would like to do(i.e create a new note, delete a note), the prompt wouldn't be displayed. Any suggestions on how I could fix this issue?

链接到项目

`

    fileDatabase = [];
    var reply;
    var FileName;
    var FileContent;

    var readline = require('readline');
    var async = require('async');

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

    class NewFile {
        constructor(fileName,fileContent){
            this.fileName = fileName
            this.fileContent = fileContent
        }
    };

    console.log("Hello! Welcome to your file management system.")

    async.whilst(

        function(){
            return reply != "5";
        },

        function(callback){ 
            rl.question("Press a number:\n1: Create a new file.\n2: View a file.\n3: Add to a file.\n4: Delete a file.\n5: Exit this program.", function(answer) {
                var reply = answer
                console.log(reply)
                rl.close();
            });

            if (reply === "1") {
                rl.question("What would you like to name this file?", function(answer){
                    var FileName = answer
                    rl.close()
                });
                rl.question("Write onto your file. You will be able to edit it later.", function(answer){
                    var FileContent = answer
                    rl.close()
                });         
            }
            setTimeout(callback, 1000);
        },

        function(err) {
             console.err("we encountered an error", err); 
        }
    )

`

推荐答案

由于您仅使用在线编辑器. (至少我正在尝试解决您提示问题的问题.)

As you are only using an online editor. (At least I am trying to solve your problem of prompting issue.)

我建议 https://www.katacoda.com/courses/nodejs/playground

将您的代码复制到app.js文件中.

Copy your code into app.js file.

您将具有Terminal选项卡.请先安装依赖项.

You will have the Terminal tab. Please install dependencies first.

npm install -g异步

npm install -g asynch

npm install -g readline

npm install -g readline

这样，您将在树下拥有node_modules文件夹.

By which, you will have node_modules folder under the tree.

然后点击左侧用黑色突出显示的node app.js链接.

And click on node app.js link left side highlighted by black color.

夫妇，您应该注意自己的代码:

1. 请尝试分配一些默认值reply，也许您可​​以将其设置为var reply = 0
2. 将列表代码包装为reply = 0的条件.
3. if (reply === "1")此条件将严格检查字符串.改用if(reply == 1).
4. 然后根据需要修改代码，以解决下一个问题.

1. Please try to assign some default value of reply maybe you can do as var reply = 0
2. Wrap the list code to the condition if reply = 0.
3. if (reply === "1") this condition will strictly check with string. use instead if(reply == 1).
4. And modify your code as per your requirement to fall into next question.

下面是修改后的代码:

fileDatabase = [];
var reply = 0;
var FileName;
var FileContent;

var readline = require('readline');
var async = require('async');

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

class NewFile {
    constructor(fileName, fileContent) {
        this.fileName = fileName;
        this.fileContent = fileContent;
    }
}

console.log('Hello! Welcome to your file management system.');

async.whilst(
    function() {
        return reply != '5';
    },

    function(callback) {
 
        if (reply === 0) {
            rl.question(
                'Press a number:\n1: Create a new file.\n2: View a file.\n3: Add to a file.\n4: Delete a file.\n5: Exit this program.\n',
                function(answer) {
                     reply = answer;
                    rl.close();
                }
            );
      }

    if (reply == 1) {
        rl.question('What would you like to name this file?\n', function(answer) {
            var FileName = answer;
            rl.close();
        });
        rl.question(
            'Write onto your file. You will be able to edit it later.\n',
            function(answer) {
                var FileContent = answer;
                rl.close();
            }
        );
    }
    setTimeout(callback, 1000);
},

    function(err) {
        console.err('we encountered an error', err);
    }
);

供参考:

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