Javascript make variable from an array of characters

Question

How you can make a variable from an array of characters in Javascript.

chars = ["a","b","c","d"];
chars[1],chars[0],chars[2] = "Hellow world";
alert(bac); // Hellow world

Why would you want to do that? Variable/dynamic variables are usually considered bad coding practice. Why not use a map instead? — Felix Kling
– Felix Kling, Commented Nov 19, 2016 at 1:30
You can't. You can set properties on an object, though. (You could eval, I suppose, but please don't.) — Dave Newton
– Dave Newton, Commented Nov 19, 2016 at 1:30
The problem is that you want to do something that isn't a good idea. So the question is why you want to do so we can suggest a better solution. "i'm using this for obfuscation" Why don't you use an existing tool for obfuscating your code? — Felix Kling
– Felix Kling, Commented Nov 19, 2016 at 1:41
"but if you search for that variable in javascript code you will not find it" - Who do you think will be searching through your code? And why? — nnnnnn
– nnnnnn, Commented Nov 19, 2016 at 1:56

user2575725 · Accepted Answer · 2016-11-19 01:47:42Z

3

There is no need for eval or map:

var chars = ["a", "b", "c", "d"];
window[chars[1] + chars[0] + chars[2]] = "Hellow world";
console.log(bac); // Hellow world

answered Nov 19, 2016 at 1:47

user2575725

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1 Comment

That's a property on an object, which is what I said, no?

salezica · Accepted Answer · 2016-11-19 01:37:26Z

1

This is absolutely not a good practice. Only do it for fun. No professional work uses code like this.

That said:

chars = ['a', 'b', 'c']
eval("window." + chars.join('') + " = 'Hello World'")
alert(abc)

Yep.

answered Nov 19, 2016 at 1:37

salezica

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No reason to use eval here, you can just use [] notation.

Haha true. I wonder why I thought of using eval. Well, @Arvind got it simpler