Recursive implementation of JSON.stringify

stringifyJSON.js

var stringifyJSON = function(object){
  // Base case: If not object and is a string,
  // wrap in quotes and return.
  // If not passed in (i.e., null),
  // return empty string.
  if(typeof object !== 'object' || object === null){
    if(typeof object === 'string'){
      object = '"' + object + '"';
    }
    return String(object);
  } else {
    // If object or array:
    var property = [];
    var value = [];
    var json = [];

    // Boolean that's toggling whether an array is passed in.
    var array = (object && object.constructor === Array);

    // For each key/value pair, if value is a string,
    // wrap in quotes and reassign. However,
    // if value is present and is, itself, an object,
    // recall function and pass it value (because it's an object).
    for(property in object){
      value = object[property];
      if(typeof value === 'string'){
        value = addEscapeChars(value);
        value = '"' + value + '"';
      } else if(typeof value === 'function' || typeof value === 'undefined'){
        delete object[property];
        return stringifyJSON(object);
        } else if(typeof value === 'object' && value !== null){
        value = stringifyJSON(value);
      }
      json.push((array ? '' : '"' + property + '":') + String(value));
    }
    // Wrap in appropriate bracket type and return.
    return (array ? '[' : '{') + String(json) + (array ? ']' : '}');
  }
};

var addEscapeChars = function(string){
  var result = [];
  var chars = string.split('');
  for(var i = 0, len = chars.length; i < len; i++){
    if(chars[i] === String.fromCharCode(34) ||
       chars[i] === String.fromCharCode(92) ){
      result.push(String.fromCharCode(92));
      result.push(chars[i]);
    } else {
      result.push(chars[i]);
    }
  }
  return result.join('');
};