JSON ignore key case

gistfile1.txt

var obj = {
    "containerIsArchived": "Null",
    "containerOrderNo": "26",
    "versionNum": "0",
	"versionnum": "01",
    "containerGlobalUniqueId": "Null",
    "containerIsTenantBased": "true",
    "containerCreatedBy": "user",
    "containerIsDeleted": "false",
    "containerTenantId": "292FEC76-5F1C-486F-85A5-09D88096F098",
    "containerLayoutId": "4e13dfcd-cd3b-4a29-81bd-0f73cf9577cf",
    "containerApplicationId": "0000000-0000-0000-0000-000000000000",
    "containerIsActive": "Null",
    "containerHeaderText": "apitest19feb16",
    "containerId": "3745b273-c48d-4c94-b576-3d7aac2f7ac6",
    "containerCreatedUTCDate": "2016-02-19 17:57:51.0"
  };  
 -------------------------------
var key, keys = Object.keys(obj);
var n = keys.length;
var objArr=[]
while (n--) {
  objArr.push(keys[n].toLowerCase());
}
--------------------------------- 
  console.time('start');
var key, keys = Object.keys(obj);
var n = 0;
var newobj={}
while (n < keys.length) {
	n++;
  key = keys[n];
  newobj[key.toLowerCase()] = obj[key];
}
console.timeEnd('start');
--------------------------------------

function ConvertKeysToLowerCase(obj) {
    var output = {};
    for (i in obj) {
        if (Object.prototype.toString.apply(obj[i]) === '[object Object]') {
           output[i.toLowerCase()] = ConvertKeysToLowerCase(obj[i]);
        }else if(Object.prototype.toString.apply(obj[i]) === '[object Array]'){
            output[i.toLowerCase()]=[];
             output[i.toLowerCase()].push(ConvertKeysToLowerCase(obj[i][0]));
        } else {
            output[i.toLowerCase()] = obj[i];
        }
    }
    return output;
};


var fault = Ext.JSON.decode(JSON.stringify(fault).replace(/"([^"]+)":/g,function($0,$1){return ('"'+$1.toLowerCase()+'":');})),

JSON.stringify(obj).replace(/"([^"]+)":/g,function($0,$1){return ('"'+$1.toLowerCase()+'":');})