Read json file ignoring custom comments

Question

How can i read this file 'file.json':

# Comment01
# Comment02
{
   "name": "MyName"
}

and retrieve the json without comments?

I'm using this code:

var fs = require('fs');
var obj;
fs.readFile('./file.json', 'utf8', function (err, data) { 
  if (err) throw err;
  obj = JSON.parse(data);
});

it returns this error:

SyntaxError: Unexpected token # in JSON at position 0

Have npm some package to solve this question?

Answer 1

The perfect package for this problem is https://www.npmjs.com/package/hjson

hjsonText input:

{
  # hash style comments
  # (because it's just one character)

  // line style comments
  // (because it's like C/JavaScript/...)

  /* block style comments because
     it allows you to comment out a block */

  # Everything you do in comments,
  # stays in comments ;-}
}

Usage:

var Hjson = require('hjson');

var obj = Hjson.parse(hjsonText);
var text2 = Hjson.stringify(obj);

Answer 2

You can use your own RegExp pretty easily to match the comments beginning with a #

const matchHashComment = new RegExp(/(#.*)/, 'gi');
const fs = require('fs');

fs.readFile('./file.json', (err, data) => {
    // replaces all hash comments & trim the resulting string
    let json = data.toString('utf8').replace(matchHashComment, '').trim();  
    json = JSON.parse(json);
    console.log(json);
});