find first sequence of "/>" in regExp, javascript

Question

I want to find an img tag in a string. I wrote for example:

var str ='<img border="1" height="165" id="img2" src="http://google.jpg"  />';
var regXstr = "<img (.)*/>";
var regX = new RegExp(regXstr , 'gi');
document.write(str.match(regX));

and the output is the whole text in str which is good in this case, but the if I switch the str with the following:

var str ='<img border="1" height="165" id="img2" src="http://google.jpg" /> /> />';

or with

var str ='<img border="1" height="165" id="img2" src="http://google.jpg"  /><span/>';

the result is still the whole text in str, and I want only the img tag - from <img till first />

Especially, *why*, when you're working in javascript - why do you not have access to the DOM, which would allow much better focused access to elements? — Damien_The_Unbeliever, Feb 22 '12 at 19:55
[positive lookahead](http://www.regular-expressions.info/refadv.html) is the solution — xkeshav, Feb 22 '12 at 19:56
Are you not using jQuery? Don't you have access to the DOM? Oh, come on! — Alexander, Feb 22 '12 at 20:34

score 1 · Accepted Answer · edited Feb 22 '12 at 20:26

1

You can try making the regex not-greedy using '?':

var regXstr = "<img (.)*?/>";

edited Feb 22 '12 at 20:26

adl

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answered Feb 22 '12 at 19:57

PinnyM

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great. Thanks! can you explain me what the '?' is doing in this case? I know it is for marking a single character – adl Feb 22 '12 at 20:00
using a '?' after a '+' or '*' tells the matcher to search for the smallest match, see http://www.javascriptkit.com/javatutors/redev2.shtml – PinnyM Feb 22 '12 at 20:03
The second pattern will will only match the string `""` because you're missing a `.` or anything that would actually consume a character. – Mike Samuel Feb 22 '12 at 20:05

find first sequence of "/>" in regExp, javascript

1 Answers1