How to get to be return and print in outside function using node js

Question

I tried one simple function in node js and pass data to one file on to another file.but its throwing undefined.how to solve it in node js

fun.js

function Get_Value()
{
    client.get('products', function(err,results) {
        return results

    })
    console.log(results)
}

I tried to print value in outside the function but its print undefined how to print result in out side function

SIMDD · Accepted Answer · 2019-05-01T05:24:10.093

0

async function Get_Value() {
  let results = await new Promise(function(resolve) {
    client.get("products", function(err, results) {
      resolve(results);
    });
  });

  console.log(results);
}

edited May 01 '19 at 05:24

answered May 01 '19 at 04:23

SIMDD

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narayansharma91 · Answer 2 · 2019-05-01T05:24:16.787

0

This is very easy using async/await features provided by ES7.

async function  Get_Value()
{
    const results = await new Promise((resolve, reject) => {
                        client.get('products', function(err,results) {
                             resolve(results);
                        })
                    });
     console.log(results);  
 }

edited May 01 '19 at 05:24

answered May 01 '19 at 04:31

narayansharma91

2,273
1
12
20

I tried it but i cant use async keyword its throwing error – smith hari May 01 '19 at 04:37
Whats the exception? – narayansharma91 May 01 '19 at 04:47
I have doubt.async syntax is differently syntax: async()=>{function } but function async get_value() is not working or me .both syntax or right or not – smith hari May 01 '19 at 05:02
Async should be placed starting of the function. – narayansharma91 May 01 '19 at 05:04
1

client.get not promise，invalid await ! – SIMDD May 01 '19 at 05:16
Please check again. – narayansharma91 May 01 '19 at 05:24

score 0 · Answer 3 · answered May 01 '19 at 05:27

Define your Get_Value to take a callback function. You then pass a callback when you're invoking Get_Value:

function Get_Value(callback) {
  client.get('products', function(err,results) {
    if (err) return callback(err)
    callback(null, results);
  })
}

function mycallback(err, data) {
  if (err) {
    // handle error
    console.error(err)
  } else {
    console.log(data);
  }
}
Get_Value(mycallback)

How to get to be return and print in outside function using node js

3 Answers3