javascript - Hide certain values in output from JSON.stringify() -

is possible exclude fields being included in json string?

here pseudo code

var x = {     x:0,     y:0,     divid:"xyz",     privateproperty1: 'foo',     privateproperty2: 'bar' } 

i want exclude privateproperty1 , privateproperty2 appearing in json string

so thought, can use stringify replacer function

function replacer(key,value) {     if (key=="privateproperty1") retun "none";     else if (key=="privateproperty2") retun "none";     else return value; } 

and in stringify

var jsonstring = json.stringify(x,replacer); 

but in jsonstring still see as

{...privateproperty1:value..., privateproperty2:value } 

i string without privateproperties in them.

the mozilla docs return undefined instead of "none":

http://jsfiddle.net/userdude/rz5px/

function replacer(key,value) {     if (key=="privateproperty1") return undefined;     else if (key=="privateproperty2") return undefined;     else return value; }  var x = {     x:0,     y:0,     divid:"xyz",     privateproperty1: 'foo',     privateproperty2: 'bar' };  alert(json.stringify(x, replacer)); 

here duplication method, in case decide go route (as per comment).

http://jsfiddle.net/userdude/644sj/

function omitkeys(obj, keys) {     var dup = {};     (key in obj) {         if (keys.indexof(key) == -1) {             dup[key] = obj[key];         }     }     return dup; }  var x = {     x:0,     y:0,     divid:"xyz",     privateproperty1: 'foo',     privateproperty2: 'bar' };  alert(json.stringify(omitkeys(x, ['privateproperty1','privateproperty2']))); 

edit - changed function key in bottom function keep being confusing.