php's http_build_query() in javascript

http_build_query.js

var build_query = function (obj, num_prefix, temp_key) {

  var output_string = []

  Object.keys(obj).forEach(function (val) {

    var key = val;

    num_prefix && !isNaN(key) ? key = num_prefix + key : ''

    var key = encodeURIComponent(key.replace(/[!'()*]/g, escape));
    temp_key ? key = temp_key + '[' + key + ']' : ''

    if (typeof obj[val] === 'object') {
      var query = build_query(obj[val], null, key)
      output_string.push(query)
    }

    else {
      var value = encodeURIComponent(obj[val].replace(/[!'()*]/g, escape));
      output_string.push(key + '=' + value)
    }

  })

  return output_string.join('&')

}