Snippet to convert a Json object to a query string for URL.

json2querystring.js

function json2querystring(json) {
  return Object.keys(json).map(function(k) { return encodeURIComponent(k) + '=' + encodeURIComponent(json[k]) }).join('&');
}

var json = {param_1:'value1', param_2:'value2', param_3:3};
console.log(json2querystring(json));