Why does String([1,2])=="1,2" and not "[1,2]"?

Question

What I want to do is change an array, say,

[1,2,[3,4],17.5]

into a sting like

"[1,2,[3,4],17.5]"

but not like

"1,2,3,4,17.5"

i.e. keeping all of the brackets. I tried using the built in String() function, but that gave me "1,2,3,4,17.5" Is there a built-in function or a code snippet that I can use to get "[1,2,[3,4],17.5]"?
Thanks!

@MadaraUchiha This is not a duplicate because this covers all arrays including things like ["meow",7,['Q',19.36]] — Sam Quinn, Jul 25 '13 at 23:44
It *is* a duplicate because the answer thre applies to your question. — Madara's Ghost, Jul 26 '13 at 07:33
@MadaraUchiha: No, that is not what a duplicate _question_ means. However, even the questions are similar enough. — Lightness Races in Orbit, Jul 26 '13 at 09:29
@LightnessRacesinOrbit: It doesn't matter what the duplicate question **means**. It matters whether or not the answer to **this** question is found in **the linked question**, which applies. The meaning of "duplicate" was changed. It's also the reason why you can't close against a duplicate with no upvoted answers. — Madara's Ghost, Jul 26 '13 at 09:30
@MadaraUchiha: Sorry but that is simply incorrect. When we mark question A as a duplicate of question B, that shall be because question A is the same as question B. Not because one or more answers on question A happens to fit question B also. The meaning of "duplicate" has not changed. We can no long close against a dup with no upvoted answers because SE recognised that marking question A as a duplicate of question B is a waste of time if doing so won't lead the OP of question A to their answer (though [this move was _widely_ condemned](http://meta.stackexchange.com/q/165928/155739)). — Lightness Races in Orbit, Jul 26 '13 at 09:31
@Jimbo: I didn't say it's not a dupe. I actually said that the questions are similar enough. I have voted to close as a dupe. I'm just saying that it's the _questions_ that matter, not the _answers_. It's called "[this question is a] duplicate of [that question]", not "[this question is not a] duplicate of [that question, but some of the answers may happen to match up!]" — Lightness Races in Orbit, Jul 26 '13 at 09:33
Why does it matter? We've, as a community, closed this as a dupe together. This discussion is over now. — Jimbo, Jul 26 '13 at 09:34
@rightfold: Well, that escalated quickly! You're welcome to discuss the finer things of this in the [PHP chat room](http://chat.stackoverflow.com/rooms/11/php). — Madara's Ghost, Jul 26 '13 at 09:35
@MadaraUchiha: And you are always welcome in the [C++ Lounge](http://chat.stackoverflow.com/rooms/10/loungec)! — Lightness Races in Orbit, Jul 26 '13 at 10:05
Final thought: it might be a good idea to mention on the duplicated question that it also applies to arrays and strings (i.e. ""Meow"") — Sam Quinn, Jul 27 '13 at 14:19

score 5 · Accepted Answer · edited May 23 '17 at 10:25

5

You want a JSON string:

array = [1,2,[3,4],17.5];
JSON.stringify( array );

See this question:

Convert JS object to JSON string

Does not work on IE 7 and lower!

edited May 23 '17 at 10:25

Community

1
1

answered Jul 25 '13 at 20:17

Tim Baas

6,035
5
45
72

2

Just add json2 for IE7 and below support https://github.com/douglascrockford/JSON-js/blob/master/json2.js – mpen Jul 25 '13 at 20:19
Thank you this is exactly what I needed! I missed that other question because I wasn't searching for JSON. – Sam Quinn Jul 25 '13 at 23:39

score 1 · Answer 2 · answered Jul 25 '13 at 20:23

If you're not worried about conflicts with other pieces of code, you could change Array.prototype.toString

(function () {
    var arrayString = Array.prototype.toString;
    Array.prototype.toString = function toString() {
        return '[' + arrayString.call(this) + ']';
    }
}());

[1,2,[3,4],17.5].toString();
// "[1,2,[3,4],17.5]"

Pablo208 · Answer 3 · 2013-07-26T10:12:22.553

0

I'm pretty sure you could create a simple method to do this if you don't want to use json , Something along the following :

(function toBracketedString(arr) {
     if (!_.isArray(arr)) { return ""; }
     var base = "[";

     for (var element in arr){
         base.append(","+element.toString());
     }
     base.append("]");
});

Hope this helps

edited Jul 26 '13 at 10:12

answered Jul 25 '13 at 20:29

Pablo208

23
6

Yes I'm aware this is crappy code I just wanted to get the idea across to you – Pablo208 Jul 25 '13 at 20:30
I don't think this is a good example.. Someone asking a question like this, isn't helped with this sort of code.. – Tim Baas Jul 25 '13 at 20:33
edited to a better coding ,@Tim – Pablo208 Jul 25 '13 at 20:51
I didn't even look at the first version, but any snippet that contains syntax errors is a bad example already. Not to mention all the other mistakes this code has (e.g. what's the point of calling `isArray()` on `arr` if it's not an array?) – Ingo Bürk Jul 25 '13 at 20:55
@IngoBürk there syntax errors fixed (I did it on the fly ). I'm trying to get the idea across not do the guys coding for him – Pablo208 Jul 25 '13 at 21:09
@Pablo208 This would be a good alternative if it worked (I'm getting an Unexpected Identifier in V8), but on a side note, it will not work for nested arrays like ["meow",7,['Q',19.36]] – Sam Quinn Jul 25 '13 at 23:48
@SamQuinn sorry used of instead of in (been using coffeescript primarily as of late) , I think node may also have issues with isArray so that may be another factior – Pablo208 Jul 26 '13 at 08:42

Why does String([1,2])=="1,2" and not "[1,2]"?

3 Answers3