javascript RegExp - get count of all html tags total characters

Question

I am trying to get the count (length) of all matching HTML characters including opening (<tag>) and closing (</tag>) including any attributes

Consider the following HTML:

<div>
    <a href="#">link</a>
    <span>some text</span>
</div>

The HTML character length count will be 40 (as it counts <div><a href="#"></a><span></span></div>)

This is the working regExp (on gskinner.com)

But when using it in javascript there is a error
See jsfiddle

Answer 1

The reason for the error is that your regex includes a positive lookbehind (?<=\s) - a feature that the Javascript implementation of regular expressions does not provide (see Mimicking Lookbehinds in Javascript). (More precisely, the error is caused by the ? following the un-escaped (, when not followed by !, = or : etc.)

The link you provided to a working example is a Flex application written in ActionScript 3 and that does include positive lookbehinds.

You also need to add the g flag to the end of your regex literal to get an array of all the matches from match, then you can sum their lengths.

Here is a working example with the positive lookbehind removed and the g flag added: jsfiddle.

It shows a length of 163 which looks about right, but I'll leave the counting to you.
You may need to add something in place of the lookbehind or otherwise edit the regex - I'll also leave you to work that out.