Stringify not working when storing named array in localstorage

Question

I have named arrays that I want store in local storage.

For example:

testla=[];

testla['aaaa']='a';

However, when I try:

console.log(JSON.stringify(testla));

This outputs:

[]

And even more weird, when using:

testla=[];

testla[10]='a';

I get strange results like this:

[null,null,null,null,null,null,null,null,null,null,"a"]

According to docs, localstorage can only store strings, therefore stringifying makes sense to me, but apparently it doesn't work, so there must be other way of doing this.

_"I have named arrays"_ - no you don't, because that's not a thing. http://stackoverflow.com/questions/874205/what-is-the-difference-between-an-array-and-an-object — CBroe, May 13 '17 at 22:15

Alex · Accepted Answer · 2017-05-13T22:17:57.870

1

JSON.stringify() ignores non-array properties of arrays. But you can use objects: var testla = {}; .

edited May 13 '17 at 22:17

answered May 13 '17 at 22:11

Alex

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I use objects to store other variables but I want to achieve this with named arrays particularly. – Anonymous May 13 '17 at 22:13

score 1 · Answer 2 · answered May 13 '17 at 22:31

In the first example you are just adding a property call aaa to your object. Same as

testla.aaaa = 'foo';

You can create an associative array by using an object as so :

var myArr = {};
myArr['aaaa'] = 'bar';

There is no such thing as a named array, arrays in js can only be indexed using numbers.

Stringify not working when storing named array in localstorage

2 Answers2