How can i assign data as variable in node?

Question

I would like the function below to return me the img so i can use it later. For now its only logged into console as:

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const QRCode = require('qrcode')

function getData(){
    QRCode.toDataURL('some string', function (err, img) {
        console.log(img)
    })
}

getData()

Answer 1

You need to assign the data to a variable after qrcode.toDataUrl() has completed. You can do that in the callback you currently have, or you can use .then(x => { }); since one of the overlaods for toDataUrl() returns a promise.

const QRCode = require('qrcode')

var data;

QRCode.toDataURL('some string').then(qr => {
    data = qr; // After toDataUrl is finished, the qr data is assigned to the data variable
});