splicing specific value in array of array

Question

I have an associative array stored in another associative array. I know how to splice a specific value in just a regular array as such:

arr.splice(arr.indexOf('specific'), 1);

I was wondering how one could splice an array such as this:

arr['hello']['world']

EDIT Would this shorten hello['world']['continent']

var hello = {};
            hello['world'] = {};
            hello['world']['continent'] = "country";
            delete hello['world']['continent'];
            alert(hello['world']['continent'])

What are `hello` and `world`? What does `arr` look like? What do you want it to look like? — gen_Eric, Mar 07 '12 at 19:48
`arr['hello']['world']` can also be accessed as `arr.hello.world` — gen_Eric, Mar 07 '12 at 20:06

score 2 · Accepted Answer · edited May 23 '17 at 10:24

2

You should be able to just just use the delete keyword.

delete arr["hello"]["world"]

How do I remove objects from a javascript associative array?

Edit, based on other comments:

For the sake of readability, you can also do:

delete arr.hello.world

Since we are really just talking about objects, and not traditional arrays, there is no array length. You can however delete a key from an object.

edited May 23 '17 at 10:24

Community

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answered Mar 07 '12 at 19:45

GoldenNewby

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would this shorten the array though? – re1man Mar 07 '12 at 19:46
It would remove the world object all together. So, it would shorten arr["hello"] – GoldenNewby Mar 07 '12 at 19:48
wouldn't it just make it undefined...im pretty sure – re1man Mar 07 '12 at 19:49
I agree with Praneet Sharma. delete sets an item undefined while splice actually "shortens". – tamarintech Mar 07 '12 at 19:50
@esnyder: JavaScript doesn't have "associative" arrays. If the key is `"hello"`, that means `arr` is an object, not an array, so it doesn't have a length (so "shorten" doesn't make sense here). – gen_Eric Mar 07 '12 at 19:52
`delete` used on an array will leave a space with `undefined`, but used on an object, it will remove the property. – gen_Eric Mar 07 '12 at 19:53
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I was thinking of the length more in the context of listing the keys of the object. In that case I believe it would shorten the list of keys. – GoldenNewby Mar 07 '12 at 19:58
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@Rocket The reason I put "shortens" in those quotes is exactly what you're suggesting... "shortens" doesn't make sense (exactly as you said). That's what I was trying to communicate. :) – tamarintech Mar 07 '12 at 20:06

score 1 · Answer 2 · answered Mar 07 '12 at 20:01

1

JavaScript does not have associative arrays.

Use objects:

var x = {
  a : 1,
  b : 2,
  c : {
     a : []
  }
}

delete x.c.a;

answered Mar 07 '12 at 20:01

max

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score 0 · Answer 3 · answered Mar 07 '12 at 19:48

0

An "associative array" in javascript isn't actually an array, it's just an object that has properties set on it. Foo["Bar"] is the same thing as Foo.Bar. So you can't really talk about slicing or length here.

answered Mar 07 '12 at 19:48

bhamlin

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splicing specific value in array of array

3 Answers3