function jsonToString (obj){
var THIS = this;
switch(typeof(obj)){
case 'string':
return '"' + obj.replace(/(["\\])/g, '\\$1') + '"';
case 'array':
return '[' + obj.map(THIS.jsonToString).join(',') + ']';
case 'object':
if(obj instanceof Array){
var strArr = [];
var len = obj.length;
for(var i=0; i<len; i++){
strArr.push(THIS.jsonToString(obj[i]));