JS uses readLine to realize terminal input data

Preface ： A while ago JS Brush problem , Encounter manual input data , I lost it , I didn't see it Js Code of manually entered data , So that it has been stuck , After several days, I met again , It can't be solved , Once or twice , So I looked up all kinds of information , But I feel that the information I'm looking for is not satisfactory , But I still learned something , I see. In Node Environmental use readline Realize single line input , But I haven't found a method of multi line input . But it can be realized by changing the environment , hold Node Environment change V8 Environmental Science . But I'm right about V8 Not really , I don't know how to replace , So don't talk too much here .

One 、 What is? readline

readline yes Node.js A encapsulated module that implements standard input and output in , Through this module, we can read the data stream line by line . Use require（“readline”） You can reference modules .

Two 、readline Use

#  install 
npm i readline

//1. introduce readline modular 
const readline = require("readline")
//2. establish readline example 
const r1 = readline.createInterface({
    
    input:process.stdin,// The standard input 
    output:process.stdout// standard output 
})
//3. call readline Related interface methods , Realize input and output 
//str What is stored in is the data we input from the terminal 
r1.question(" Please input data ：",function(str){
    
    console.log(" The data you entered is ：",str);
    // End output , This method must be called , otherwise readline Will be waiting for you to enter 
    r1.close()
})
//4. monitor readline Related events 
r1.on("close",function(){
    
    // sign out 
    process.exit(0);
})

Operation mode ：

#  The input terminal 
node Js file 

Running results ：

give an example ： Manual input , Find the sum of two numbers

const readline= require('readline')

const r1 = readline.createInterface({
    
  input:process.stdin,
  output:process.stdout
})

r1.question(' Please input data ：', function(sum) {
    
  let arr = sum.split(' ')
  var all = 0;
  for(let i=0 ;i<arr.length; i++){
    
    all+= Number(arr[i])
  }
  console.log(` The result of the addition is ：${
      all}`)
  r1.close()

})

r1.on("close",function(){
    
  process.exit(0);
}) 

Running results ：

Expand

V8 Multi line input in environment 

while(line=readline()){
    
    var lines = line.split(' ');
    var a = parseInt(lines[0]);
    var b = parseInt(lines[1]);
    print(a+b);
}

Related information

https://blog.csdn.net/rraxx/article/details/115051515?ops_request_misc=&request_id=&biz_id=102&utm_term=JS%20read_line&utm_medium=distribute.pc_search_result.none-task-blog-2_allsobaiduweb~default-4-115051515.142^v33pc_search_result_control_group,185^v2control&spm=1018.2226.3001.4187

https://www.nowcoder.com/discuss/276