Javascript equivalent of Python's values() dictionary method

Question

In Python I can use the .values() method to iterate over the values of a dictionary.

For example:

mydict = {'a': [3,5,6,43,3,6,3,],
          'b': [87,65,3,45,7,8],
          'c': [34,57,8,9,9,2],}
values = mydict.values():

Where values contains:

[
    [3,5,6,43,3,6,3,],
    [87,65,3,45,7,8],
    [34,57,8,9,9,2],
]

How can I get only the values of the dictionary in Javascript?

My original print example wasn't clear on what I'd like to do. I only want a list/array of the values within the dictionary.

I realize I can cycle through the list and create a new list of the values, but is there a better way?

@Oriol I disagree with this closure. This one specifically asks about returning to an array. Granted, not all the answers address that properly. The other question wants to access it from a loop. I think this is shown by the fact that [my answer](http://stackoverflow.com/a/28414954/3187556) applies to this question but not the target. — Scimonster, Feb 09 '15 at 17:03
@Scimonster The [most upvoted answer](http://stackoverflow.com/a/16643074/1529630) in the other question answers this perfectly. It even includes a variation of your answer to this question. You can vote to reopen if you disagree, though. — Oriol, Feb 09 '15 at 17:07

Jibi Abraham · Accepted Answer · 2012-07-31T07:21:53.403

109

Updated
I've upvoted Adnan's answer as it was the first. I'm just posting a bit more details if it helps.

The for..in loop is what you are looking for -

var dictionary = {
    id:'value',
    idNext: 'value 2'
}

for (var key in dictionary){
    //key will be -> 'id'
    //dictionary[key] -> 'value'
}

To get all the keys in the dictionary object, you can Object.keys(dictionary)
This means, you can do the same thing in an array loop --

var keys = Object.keys(dictionary);
keys.forEach(function(key){
    console.log(key, dictionary[key]);
});

This proves especially handy when you want to filter keys without writing ugly if..else loops.

keys.filter(function(key){
    //return dictionary[key] % 2 === 0;
    //return !key.match(/regex/)
    // and so on
});

Update - To get all the values in the dictionary, currently there is no other way than to perform a loop. How you do the loop is a matter of choice though. Personally, I prefer

var dictionary = {
    a: [1,2,3, 4],
    b:[5,6,7]
}
var values = Object.keys(dictionary).map(function(key){
    return dictionary[key];
});
//will return [[1,2,3,4], [5,6,7]]

edited Jul 31 '12 at 07:21

answered Jul 31 '12 at 06:45

Jibi Abraham

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Upvoting isn't about who's first. If the answer is helpful & useful then it's wroth upvoting, pretty much like yours xdazz's – Adi Jul 31 '12 at 06:57
Object.keys(dictionary).map can be made prettier in jQuery! Check out http://stackoverflow.com/a/18063034/764463 – Temuz Aug 05 '13 at 16:27
4

@Temuz, http://needsmorejquery.com/ – crenshaw-dev Jan 05 '18 at 19:54
@mac9416 oh boy you really showed that 2013 comment who's boss! – Temuz Jan 06 '18 at 20:44
@Temuz touché. :-) – crenshaw-dev Jan 07 '18 at 21:40
@mac9416, did someone really pay for level 2 domain name to host only a pair of static files?! – ogurets Nov 30 '18 at 19:53
1

@ogurets folks be salty. – crenshaw-dev Nov 30 '18 at 20:25
@MichaelCrenshaw Money well spent I say; both on comedic and educational value :D thanks for sharing. Every time I read jquery these days I hear that line from Butt Machine by That One Guy: "And just because we can, it doesn't mean we should" – nevelis Jul 31 '19 at 01:30

score 38 · Answer 2 · edited Sep 14 '18 at 05:30

38

Object.values() is available in Firefox 47 and Chrome 51, here's a one-line polyfill for other browsers:

Object.values = Object.values || function(o){return Object.keys(o).map(function(k){return o[k]})};

edited Sep 14 '18 at 05:30

Paul Rooney

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answered May 21 '14 at 10:37

user

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score 27 · Answer 3 · edited Nov 17 '15 at 22:59

27

With jQuery, there's a pretty one line version using $.map():

var dict = {1: 2, 3: 4};
var values = $.map(dict, function(value, key) { return value });
var keys = $.map(dict, function(value, key) { return key });

edited Nov 17 '15 at 22:59

XPX-Gloom

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answered Aug 05 '13 at 16:23

Temuz

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The most elegant solution – Jérôme Pouiller Feb 03 '16 at 16:12

CatShoes · Answer 4 · 2014-07-23T19:44:25.163

13

Not trying to say that any of the other answers are wrong, but if you're not opposed to using an external library, underscore.js has a method for precisely this:

_.values({one: 1, two: 2, three: 3});
// returns [1, 2, 3]

edited Jul 23 '14 at 19:44

answered Jul 23 '14 at 18:37

CatShoes

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score 6 · Answer 5 · answered Jul 31 '12 at 06:38

6

You can use for in

mydict = {'a': [3,5,6,43,3,6,3,],
          'b': [87,65,3,45,7,8],
          'c': [34,57,8,9,9,2]};
for (var key in mydict){
    alert(mydict[key]);
}

answered Jul 31 '12 at 06:38

Adi

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score 5 · Answer 6 · edited Apr 13 '17 at 12:38

5

In ES6, currently supported by default in Firefox and with flags in Chrome, you can do this:

a = {'a': [3,5,6,43,3,6,3,],
      'b': [87,65,3,45,7,8],
      'c': [34,57,8,9,9,2]}
values = [a[x] for (x in a)];

values will now be the expected array.

This is also useful for code golf. Removing the spaces around for cuts it down to 17 characters.

edited Apr 13 '17 at 12:38

Community

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answered Feb 09 '15 at 16:51

Scimonster

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score 3 · Answer 7 · answered Jul 31 '12 at 06:38

3

In javascript, you use for..in to loop the properties of an object.

var mydict = {
    'a': [3,5,6,43,3,6,3,],
    'b': [87,65,3,45,7,8],
    'c': [34,57,8,9,9,2]
 };

for (var key in mydict) {
  console.log(mydict[key]);
}

answered Jul 31 '12 at 06:38

xdazz

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`console.log()` I forget about it every time, +1 – Adi Jul 31 '12 at 06:39

score 1 · Answer 8 · answered Jan 08 '14 at 12:25

1

if you want to get only the values the use the follwing code:

 for(keys in mydict){
   var elements = mydict[keys];
   console.log(elements);
 }

you can get Individual elements by index value in elements array.

answered Jan 08 '14 at 12:25

BeingNerd

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Javascript equivalent of Python's values() dictionary method

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