blocks|key|4422688|text|不需要另一个变量，只需像这样使用：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4422689|const+readline+=+require('readline');

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

rl.question('Please+enter+the+first+number+:+',+(answer1)+=>+{
++++rl.question('Please+enter+the+second+number+:+',+(answer2)+=>+{
++++++++var+result+=+(%2Banswer1)+%2B+(%2Banswer2);
++++++++console.log(`The+sum+of+above+two+numbers+is+${result}`);
++++++++rl.close();
++++});
});|code-block|syntax|javascript|4422690|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

No need another variable, just use like this:

<pre><code>const readline = require('readline');

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

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

blocks|key|4422750|text|嵌套的代码/回调很难阅读和维护，这里有一种更优雅的方式来使用Promise来提出多个问题|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4422751|节点8%2B|4422752|'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()|code-block|syntax|javascript|4422753|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Nested code/callback are terrible to read and maintain, here's a more elegant way to use Promise for asking multiple questions

node 8+

<pre><code>'use strict'

const readline = require('readline')

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

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

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

const main = async () =&gt; {
 await question1()
 await question2()
 rl.close()
}

main()
</code></pre>

blocks|key|4422609|text|对于那些感兴趣的人，我把这个小模块放在一起，它接受一组问题，并返回一个解决一组答案的承诺：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4422610|const+readline+=+require('readline');

const+AskQuestion+=+(rl,+question)+=>+{
++++return+new+Promise(resolve+=>+{
++++++++rl.question(question,+(answer)+=>+{
++++++++++++resolve(answer);
++++++++});
++++});
}

const+Ask+=+function(questions)+{
++++return+new+Promise(async+resolve+=>+{
++++++++let+rl+=+readline.createInterface({
++++++++++++input:+process.stdin,
++++++++++++output:+process.stdout
++++++++});

++++++++let+results+=+[];
++++++++for(let+i=0;i+<+questions.length;i%2B%2B)+{
++++++++++++const+result+=+await+AskQuestion(rl,+questions[i]);
++++++++++++results.push(result);
++++++++}
++++++++rl.close();
++++++++resolve(results);
++++})
}

module.exports+=+{
++++askQuestions:+Ask+
}|code-block|syntax|javascript|4422611|将其保存在一个名为ask.js+(或您喜欢的任何文件)的文件中，并按如下方式使用：|4422612|const+{+askQuestions+}+=+require('./ask');

askQuestions([
+++'What+is+question+1?',
+++'What+is+question+2?',
+++'What+is+question+3?'
])
++++.then(answers+=>+{
++++++++//+Do+whatever+you+like+with+the+array+of+answers
++++});|4422613|注意:我需要一个转译器或最新版本的Node，因为它使用了大量的ES6特性。|4422614|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

For those interested I put together this little module that takes an array of questions and returns a promise that resolves to an array of answers:

<pre><code>const readline = require('readline');

const AskQuestion = (rl, question) =&gt; {
 return new Promise(resolve =&gt; {
 rl.question(question, (answer) =&gt; {
 resolve(answer);
 });
 });
}

const Ask = function(questions) {
 return new Promise(async resolve =&gt; {
 let rl = readline.createInterface({
 input: process.stdin,
 output: process.stdout
 });

 let results = [];
 for(let i=0;i &lt; questions.length;i++) {
 const result = await AskQuestion(rl, questions[i]);
 results.push(result);
 }
 rl.close();
 resolve(results);
 })
}

module.exports = {
 askQuestions: Ask 
}
</code></pre>

Save that in a file called ask.js (or whatever you like) and use like this:

<pre><code>const { askQuestions } = require('./ask');

askQuestions([
 'What is question 1?',
 'What is question 2?',
 'What is question 3?'
])
 .then(answers =&gt; {
 // Do whatever you like with the array of answers
 });
</code></pre>

Note: Will need a transpiler or recent version of Node as it uses a lot of ES6 features.

blocks|key|4422813|text|你可以使用递归：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4422814|var+fs+=+require('fs')
var+readline+=+require('readline')


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

+var+keys+=+[]
function+gen(rank){
++if(rank+>+3)
++++{
++++++++//do+whatever+u+want
++++++++var+sum_avg+=+0
++++++++for+(i+in+keys)
+++++++++++++{
++++++++++++++++sum_avg%2B=Number(keys[i])
+++++++++++++}
+++++++++console.log(sum_avg/3);+
+++++++++return+-1;+++++
++++}
++++else+
++++{+
++++++++var+place+=+rank>1+?+"th"+:+"st"
++++++++var+total+=+rank%2Bplace+
++++++++rl.question("Please+enter+the+"%2Btotal%2B+"+number+:",function(answer){
++++++++++++keys.push(answer)
++++++++++++//this+is+where+the+recursion+works
+++++++++++++gen(rank%2B1)
++++++++})
+++++}
++}

//pass+the+value+from+where+you+want+to+start
++gen(1)|code-block|syntax|javascript|4422815|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

you could use recursion : 

<pre><code>var fs = require('fs')
var readline = require('readline')


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

 var keys = []
function gen(rank){
 if(rank &gt; 3)
 {
 //do whatever u want
 var sum_avg = 0
 for (i in keys)
 {
 sum_avg+=Number(keys[i])
 }
 console.log(sum_avg/3); 
 return -1; 
 }
 else 
 { 
 var place = rank&gt;1 ? "th" : "st"
 var total = rank+place 
 rl.question("Please enter the "+total+ " number :",function(answer){
 keys.push(answer)
 //this is where the recursion works
 gen(rank+1)
 })
 }
 }

//pass the value from where you want to start
 gen(1)
</code></pre>

blocks|key|4422867|text|我会在一个异步函数中提出问题，并包装readline，类似于Jason上面是如何做的。虽然代码稍微少了一点:)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4422868|const+readline+=+require('readline');
rl+=+readline.createInterface({
++++input+:+process.stdin,
++++output+:+process.stdout+
+});

function+question(theQuestion)+{
++++return+new+Promise(resolve+=>+rl.question(theQuestion,+answ+=>+resolve(answ)))
}

async+function+askQuestions(){
++++var+answer+=+await+question("A+great+question")
++++console.log(answer);
}|code-block|syntax|javascript|4422869|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I would ask the questions in an async function and wrap readline similarly to how Jason did it above. Although with slightly less code :)

<pre><code>const readline = require('readline');
rl = readline.createInterface({
 input : process.stdin,
 output : process.stdout 
 });

function question(theQuestion) {
 return new Promise(resolve =&gt; rl.question(theQuestion, answ =&gt; resolve(answ)))
}

async function askQuestions(){
 var answer = await question("A great question")
 console.log(answer);
}
</code></pre>

blocks|key|4422880|text|const+readline+=+require("readline")

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

var+questions+=+[
+"Input+first+number",
+"Input+second+number",
+"Input+third+number",
+"Input+fourth+number",
+"Input+fifth+number",
];

const+askQuestion+=+(theQuestion)+=>+{
++++return+new+Promise((resolve,+reject)+=>+{
++++++++try+{
++++++++++rl.question(theQuestion+%2B+":+",+theAnswer+=>+resolve(theAnswer));
++++++++}+catch+{
++++++++++reject("No+Answer");
++++++++}
++++})
}

async+function+start(){
++++const+answers+=+[];
++++for+(question+of+questions){
++++++++answers.push(await+askQuestion(question));
++++}
++++
++++const+total+=+answers.reduce((a,+b)+=>+{return+Number(a)+%2B+Number(b)});+
++++console.log(+`The+sum+of+array+${answers}+is+${total}`);
++++rl.close();
}

start();|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|4422881|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>const readline = require(&quot;readline&quot;)

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

var questions = [
 &quot;Input first number&quot;,
 &quot;Input second number&quot;,
 &quot;Input third number&quot;,
 &quot;Input fourth number&quot;,
 &quot;Input fifth number&quot;,
];

const askQuestion = (theQuestion) =&gt; {
 return new Promise((resolve, reject) =&gt; {
 try {
 rl.question(theQuestion + &quot;: &quot;, theAnswer =&gt; resolve(theAnswer));
 } catch {
 reject(&quot;No Answer&quot;);
 }
 })
}

async function start(){
 const answers = [];
 for (question of questions){
 answers.push(await askQuestion(question));
 }
 
 const total = answers.reduce((a, b) =&gt; {return Number(a) + Number(b)}); 
 console.log( `The sum of array ${answers} is ${total}`);
 rl.close();
}

start();
 
</code></pre>

blocks|key|4422892|text|const+readline+=+require('readline');

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

const+q0+=+'What\'s+your+name?+Nicknames+are+also+acceptable+:)';
const+q1+=+'What\'s+an+activity+you+like+doing?';
const+q2+=+'What+do+you+listen+to+while+doing+that?';
const+q3+=+'Which+meal+is+your+favourite+(eg:+dinner,+brunch,+etc.)';
const+q4+=+'What\'s+your+favourite+thing+to+eat+for+that+meal?';
const+q5+=+'Which+sport+is+your+absolute+favourite?';
const+q6+=+'What+is+your+superpower?+In+a+few+words,+tell+us+what+you+are+amazing+at!';

const+arr+=+[q0,+q1,+q2,+q3,+q4,+q5,+q6];
let+res+=+'';
const+askQ+=+i+=>+{
++if+(i+<+arr.length)+{
++++rl.question(arr[i],+(answer)+=>+{
++++++res+%2B=+'\n'+%2B+answer;
++++++askQ(i+%2B+1);
++++});
++}+else+{
++++++console.log(`Thank+you+for+your+valuable+feedback:+${res}`);
++++++rl.close();
++}
};
askQ(0);|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|4422893|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>const readline = require('readline');

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

const q0 = 'What\'s your name? Nicknames are also acceptable :)';
const q1 = 'What\'s an activity you like doing?';
const q2 = 'What do you listen to while doing that?';
const q3 = 'Which meal is your favourite (eg: dinner, brunch, etc.)';
const q4 = 'What\'s your favourite thing to eat for that meal?';
const q5 = 'Which sport is your absolute favourite?';
const q6 = 'What is your superpower? In a few words, tell us what you are amazing at!';

const arr = [q0, q1, q2, q3, q4, q5, q6];
let res = '';
const askQ = i =&gt; {
 if (i &lt; arr.length) {
 rl.question(arr[i], (answer) =&gt; {
 res += '\n' + answer;
 askQ(i + 1);
 });
 } else {
 console.log(`Thank you for your valuable feedback: ${res}`);
 rl.close();
 }
};
askQ(0);
</code></pre>

blocks|key|4422922|text|const+readline+=+require('readline')

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

const+question+=+(question)+=>+{
++return+new+Promise((resolve,+reject)+=>+{
++++rl.question(question,+(answer)+=>+{
++++++resolve(answer)
++++})
++})
}

const+main+=+async+()+=>+{
++const+username+=+await+question('Please+enter+a+username:+');
++const+password+=+await+question('Please+enter+a+password:+');
++console.log("result:+",+{
++++++"username"+:+username,
++++++"password"+:+password
++});
++rl.close()
}

main()|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|4422923|我决定简化@jc为想要从问题中获得输出的开发人员编写的代码。|unstyled|4422924|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>const readline = require('readline')

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

const question = (question) =&gt; {
 return new Promise((resolve, reject) =&gt; {
 rl.question(question, (answer) =&gt; {
 resolve(answer)
 })
 })
}

const main = async () =&gt; {
 const username = await question('Please enter a username: ');
 const password = await question('Please enter a password: ');
 console.log(&quot;result: &quot;, {
 &quot;username&quot; : username,
 &quot;password&quot; : password
 });
 rl.close()
}

main()
</code></pre>
I have decided to simplify the code which @jc have written for developers that want to get an output out from the question.

I am creating a program to take input of two numbers from the command line and then showing there sum in node.js. I am using readline module to take stdin. Below is my code.

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

This program just show me "Please enter the first number" and when i enter a number like 5, it takes 5 for second input also and shows the answer 10

It don't ask second question at all. Please check this and tell me what is the problem. And if there is any better way to take multiple input please tell that.

I am a novice user in node.js

How to take two consecutive input with the readline module of node.js?

我正在创建一个程序，从命令行接受两个数字的输入，然后在node.js中显示sum。我使用readline模块来获取stdin。下面是我的代码。const readline = require('readline');const rl = readline.createInterface({    input: proc...

问如何使用node.js的readline模块接受两个连续的输入？
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问如何使用node.js的readline模块接受两个连续的输入？
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