JSON array in Node.js

Question

I have been trying to figure this out for the past week and everything that i try just doesn\'t seem to work.

I have to create a web service on my local box that re

Answer 1

edit: one-liner (try it in repl!)

JSON.stringify(JSON.parse(require('querystring').parse('theArray=%5B%5B%5D%2C"d"%2C"B"%2C%7B%7D%2C"b"%2C12%2C"A"%2C"c"%5D').theArray).filter(function(el) {return typeof(el) == 'string'}));

code to paste to your server:

case '/sort':
        if (req.method == 'POST') {
            buff = '';
            req.on('data', function(chunk) { buff += chunk.toString() });
            res.on('end', function() {
              var inputJsonAsString = qs.parse(fullArr).theArray;
              // fullArr is x-www-form-urlencoded string and NOT a valid json (thus undefined returned from JSON.parse)
              var inputJson = JSON.parse(inputJsonAsString);
              var stringsArr = inputJson.filter(function(el) {return typeof(el) == 'string'});
              res.writeHead(200,{
                'Content-Type': 'application/json',
                'Access-Control-Allow-Origin': '*'
              });
              res.end(JSON.stringify(stringsArr));
        };
break;

Answer 2

The replacer parameter of JSON.stringify doesn't work quite like you're using it; check out the documentation on MDN.

You could use Array.prototype.filter to filter out the elements you don't want:

var arr = [[],"d","B",{},"b",12,"A","c"];
arr = arr.filter(function(v) { return typeof v == 'string'; });
arr // => ["d", "B", "b", "A", "c"]

Answer 3

Edit: Try this:

var query = {"theArray":"[[],\"d\",\"B\",{},\"b\",12,\"A\",\"c\"]"};
var par = JSON.parse(query.theArray);
var stringArray = [];
for ( var i = 0; i < par.length; i++ ) {
    if ( typeof par[i] == "string" ) {
        stringArray.push(par[i]);
    }
}
var jsonString = JSON.stringify( stringArray );
console.log(jsonString);

P.S. I didnt't pay attention. Your array was actually a string. Andrey, thanks for the tip.