String equality returning false when strings are equal

Question

I have an anchor element :

<a id="buyBtn" href="#" alt="Purchase" title="Buy now" data-enabled="true">

When it is clicked, I'm doing this:

enabled = $(this).data('enabled') == "true";
console.log(enabled);

However, the console shows false. I was initially using === but that was giving false, so I moved to ==.

What do you get from `console.log($(this).data('enabled'))`? — jahroy, Oct 19 '12 at 04:46
Working example showing what's at play here: http://jsfiddle.net/FsP3j/1/ — Cᴏʀʏ, Oct 19 '12 at 04:48
@Cthulhu - The issue, in reality, is the OP did `=== "true"` instead of `=== true`. Face, meet palm, doh si doh. — Jared Farrish, Oct 19 '12 at 04:51
@Cthulhu: That's not the issue at hand. The issue was that jquery automatically converts the string 'true' to boolean `true`. — Ayush, Oct 19 '12 at 04:51

score 10 · Accepted Answer · edited May 23 '17 at 12:27

10

The accepted answer for this question details why:

jQuery's .data() method is smart enough to convert "true"/"false" data strings into real Boolean values.

The strict comparison operator checks types, and is failing because you are comparing a string to a boolean.

"true" === true // false

edited May 23 '17 at 12:27

Community

answered Oct 19 '12 at 04:46

Matt Stone

oh, wow...sheesh. I would never have guessed that. Thank you. – Ayush Oct 19 '12 at 04:47

1 Answers1