Convert object string to JS object

Question

Here is a string:

"{aa:function(){},bb:document.body}"

JSON.parse doesn't work for this,how to convert it to JS object?

@FeiSun: Well how are you using `eval`... put your real attempts in your question, don't just say you tried them cause you may have tried them wrong! Also, even if you could convert it, what do you expect to do with it? It won't be assigned to anything that you can reference anyway — musefan, Apr 18 '18 at 09:05
But it's a valid JS object form,it should can be converted to JS object. — Fei Sun, Apr 18 '18 at 09:07
No its not valid - See: https://de.wikipedia.org/wiki/JavaScript_Object_Notation I think youre mixing up the things. — Mario Murrent, Apr 18 '18 at 09:10
@FeiSun Not everything that may look like JSON actually is JSON. Your string contains a **function** and an **object reference**. Both of these are invalid and impossible in valid JSON. JSON is a data notation, not executable code! — Peter B, Apr 18 '18 at 09:14
@PeterB: Again... OP never said it was valid JSON! Only said they had tried JSON.parse, which is not the same thing — musefan, Apr 18 '18 at 09:17
Trying to use `JSON.parse` is a (possibly implicit and unaware) assumption that something is JSON. — Peter B, Apr 18 '18 at 09:18

score 2 · Accepted Answer · answered Apr 18 '18 at 09:06

2

You could use eval with a prepended assingment.

Caveat: Why is using the JavaScript eval function a bad idea?

var string = "{aa:function(){},bb:document.body}",
    object;
    
eval('object = ' + string);

console.log(object);

answered Apr 18 '18 at 09:06

Nina Scholz

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To complete your answer, it can also be achieved with ```var obj = eval('(' + string + ')')```. (Using parantheses so that the object is not parsed as a block) – Stefan Octavian Apr 18 '18 at 09:11

Asons · Answer 2 · 2018-04-18T09:31:35.383

1

An option in this case could be to use new Function().

It is less evil than eval(), and here is an answer with an explanation about their difference:

Are eval() and new Function() the same thing?

Stack snippet

var string = "{aa:function(){},bb:document.body}",
    object;
    
object = new Function( 'return (' + string + ')' )();

console.log(object);

edited Apr 18 '18 at 09:31

answered Apr 18 '18 at 09:24

Asons

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score 0 · Answer 3 · answered Apr 18 '18 at 09:22

0

In case you need to treat the string as a json object:

let str = "{\"aa\":\"function() { console.log('Look mama no hands'); }\",\"bb\":\"document.body\"}";
let obj = JSON.parse(str);
let func = null;
eval("func = "+obj.aa);
func();

answered Apr 18 '18 at 09:22

Felipe Plazas

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Convert object string to JS object

3 Answers3