How to parse JSON using Node.js? [closed]

Answer 1

I'd like to mention that there are alternatives to the global JSON object. JSON.parse and JSON.stringify are both synchronous, so if you want to deal with big objects you might want to check out some of the asynchronous JSON modules.

Have a look: https://github.com/joyent/node/wiki/Modules#wiki-parsers-json

Answer 2

My solution:

var fs = require('fs');
var file = __dirname + '/config.json';

fs.readFile(file, 'utf8', function (err, data) {
    if (err) {
        console.log('Error: ' + err);
        return;
    }

    data = JSON.parse(data);

    console.dir(data);
});

Answer 3

Another example of JSON.parse :

var fs = require('fs');
var file = __dirname + '/config.json';

fs.readFile(file, 'utf8', function (err, data) {
  if (err) {
    console.log('Error: ' + err);
    return;
  }

  data = JSON.parse(data);

  console.dir(data);
});

Answer 4

Since you don't know that your string is actually valid, I would put it first into a try catch. Also since try catch blocks are not optimized by node, i would put the entire thing into another function:

function tryParseJson(str) {
    try {
        return JSON.parse(str);
    } catch (ex) {
        return null;
    }
}

OR in "async style"

function tryParseJson(str, callback) {
    process.nextTick(function () {
      try {
          callback(null, JSON.parse(str));
      } catch (ex) {
          callback(ex)
      }
    })
}

Answer 5

As mentioned in the above answers, We can use JSON.parse() to parse the strings to JSON But before parsing, be sure to parse the correct data or else it might bring your whole application down

it is safe to use it like this

let parsedObj = {}
try {
    parsedObj = JSON.parse(data);
} catch(e) {
    console.log("Cannot parse because data is not is proper json format")
}

Answer 6

You can use JSON.parse() (which is a built in function that will probably force you to wrap it with try-catch statements).

Or use some JSON parsing npm library, something like json-parse-or