javascript - Is there any possibility to have JSON.stringify preserve functions?

Question

Take this object:

x = {
 "key1": "xxx",
 "key2": function(){return this.key1}
}

If I do this:

y = JSON.parse( JSON.stringify(x) );

Then y will return { "key1": "xxx" }. Is there anything one could do to transfer functions via stringify? Creating an object with attached functions is possible with the "ye goode olde eval()", but whats with packing it?

Answer 1

json-stringify-function is a similar post to this one.

A snippet discovered via that post may be useful to anyone stumbling across this answer. It works by making use of the replacer parameter in JSON.stringify and the reviver parameter in JSON.parse.

More specifically, when a value happens to be of type function, .toString() is called on it via the replacer. When it comes time to parse, eval() is performed via the reviver when a function is present in string form.

var JSONfn;
if (!JSONfn) {
    JSONfn = {};
}

(function () {
  JSONfn.stringify = function(obj) {
    return JSON.stringify(obj,function(key, value){
            return (typeof value === 'function' ) ? value.toString() : value;
        });
  }

  JSONfn.parse = function(str) {
    return JSON.parse(str,function(key, value){
        if(typeof value != 'string') return value;
        return ( value.substring(0,8) == 'function') ? eval('('+value+')') : value;
    });
  }
}());

Code Snippet taken from Vadim Kiryukhin's JSONfn.js or see documentation at Home Page