Regex capture string between delimiters and excluding them

Question

I saw in this forum an answare close to my "request" but not enough (Regexp to capture string between delimiters).

My question is: I have an HTML page and I would get only the src of all "img" tags of this page and put them in one array without using cheerio (I'm using node js).

The problem is that i would prefer to exclude the delimiters. How could i resolve this problem?

In most environments you would simply put the delimiters inside [lookaround assertions](http://www.regular-expressions.info/lookaround.html) – lookahead `(?=)` for the ending delimiter and lookbehind `(?<=)` for the starting delimiter. However, JavaScript does not support lookbehind, so you will need a workaround, such as [capture groups](http://www.regular-expressions.info/brackets.html). — Rory O'Kane, Jun 16 '17 at 22:34
For now i'm using this: var images = data.match(/src="(.*).jpg"/g); — Davide Modesto, Jun 17 '17 at 07:55
If anybody want to know what i'm trying to do and want to help me in this project can contact me on skype — Davide Modesto, Jun 17 '17 at 07:57

score 0 · Answer 1 · answered Jun 16 '17 at 23:34

Yes this is possible with regex, but it would be much easier (and probably faster but don't quote me on that) to use a native DOM method. Let's start with the regex approach. We can use a capture group to easily parse the src of an img tag:

var html = `test<div>hello</div>
<img src="first">
<img class="test" src="second" data-lang="en">
test
<img src="third" >`;
var srcs = [];
html.replace(/<img[^<>]*src=['"](.*?)['"][^<>]*>/gm, (m, $1) => { srcs.push($1) })

console.log(srcs);

However, the better way would be to use getElementsByTagName:
(note the following will get some kind of parent domain url since the srcs are relative/fake but you get the idea)

var srcs = [].slice.call(document.getElementsByTagName('img')).map(img => img.src);

console.log(srcs);

test<div>hello</div>
<img src="first">
<img class="test" src="second" data-lang="en">
test
<img src="third" >

Ty very much at all. I'm not using cheerio because i think it's much slower. I get an HTML page with request module then i just want to extract all the src of every images. — Davide Modesto, Jun 17 '17 at 07:27

Regex capture string between delimiters and excluding them

1 Answers1