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JavaScript RegEx match unless wrapped with [nocode][/nocode] tags

My current code is:
var user_pattern = this.settings.tag;
user_pattern = user_pattern.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&"); // escape regex
var pattern = new RegExp(user_pattern.replace(/%USERNAME%/i, "(\\S+)"), "ig");
Where this.settings.tag is a string such as "[user=%USERNAME%]" or "#%USERNAME%". The code uses pattern.exec(str) to find any username in the corresponding tag and works perfectly fine. For example, if str = "Hello, [user=test]" then pattern.exec(str) will find test.
This works fine, but I want to be able to stop it from matching if the string is wrapped in [nocode][/nocode] tags. For example, if str = "[nocode]Hello, [user=test], how are you?[/nocode]" thenpattern.exec(str)` should not match anything.
I'm not quite sure where to start. I tried using a (?![nocode]) before and after the pattern, but to no avail. Any help would be great.

I would just test if the string starts with [nocode] first:
/^\[nocode\]/.test('[nocode]');
Then simply do not process it.

Maybe filter out [nocode] before trying to find the username(s)?
pattern.exec(str.replace(/\[nocode\](.*)\[\/nocode\]/g,''));
I know this isn't exactly what you asked for because now you have to use two separate regular expressions, however code readability is important too and doing it this way is definitely better in that aspect. Hope this helps 😉
JSFiddle: http://jsfiddle.net/1f485Lda/1/
It's based on this: Regular Expression to get a string between two strings in Javascript

difference between ruby regex and javascript regex

I made this regular expression: /.net.(\w*)/
I'm trying to capture the qa in a string like this:
https://xxxxxx.cloudfront.net/qa/club/Slide1.PNG
I'm doing .replace on it like so location.replace(/.net.(\w*)/,data.newName));
But instead of capturing qa, it captures .net, when I run the code in Javascript
According to this online regex tool made for ruby, it captures qa as intended
http://rubular.com/r/ItrG7BRNRn
What's the difference between Javascript regexes and Ruby regexes, and how can I make my regex work as intended in javascript?
Edit:
I changed my code to this:
var str = `https://xxxxxxxxxx.cloudfront.net/qa/club`;
var re = /\.net\/([^\/]*)\//;
console.log(data2.files[i].location.replace(re,'$1'+ "test"));
And instead of
https://dm7svtk8jb00c.cloudfront.net/test/club
I get this:
https://dm7svtk8jb00c.cloudfrontqatestclub
If I remove the $1 I get https://dm7svtk8jb00c.cloudfronttestclub, which is closer, but I want to keep the slashes.

This would be a better regex:
/\.net\/([^\/]*)\//
Remember that . will match any character, not the period character. For that you need to escape it with a leading backslash: \.
Also, \w will only match numbers, letters and underscores. You could quite legitimately have a dash in that part of the URL. Therefore you're far better off matching anything that isn't a forward slash.

I am not sure how Ruby works, but JavaScript replace will not just replace the capture group, it replaces the whole matched string. By adding another capture group, you can use $1 to add back in the string you want to keep.
...replace(/(.net.)(\w*)/,"$1" + data.newName");

You have to do that like this:
location.replace(/(\.net.)(\w*)/, '$1' + data.newName)
replace replaces the whole matched substring, not a particular group. Ruby works exactly in the same way:
ruby -e "puts 'https://xxxxxx.cloudfront.net/qa/club/Slide1.PNG'.sub(/.net.(\w*)/, '##')"
https://xxxxxx.cloudfront##/club/Slide1.PNG
ruby -e "puts 'https://xxxxxx.cloudfront.net/qa/club/Slide1.PNG'.sub(/(.net.)(\w*)/, '\\1' + '##')"
https://xxxxxx.cloudfront.net/##/club/Slide1.PNG

There's no difference (at least with the pattern you've provided). In both cases, the expression matches ".net/qa", with qa being the first capture group within the expression. Notice that even in your linked example the entire match is highlighted.
I'd recommend something like this:
location.replace(/(.net.)\w*/, "$1" + data.newName);
Or this, to be a bit safer:
location.replace(/(.net.)\w*/, function(m, a) { return a + data.newName; });

It's not so much a different between JavaScript and Ruby's implementations of regular expressions, it's your pattern that needs a bit of work. It's not tight enough.
You can use something like /\.net\/([^\/]+)/, which you can see in action at Rubular.
That returns the characters delimited by / following .net.
Regex patterns are very powerful, but they're also fraught with dangerous side-effects that open up big holes easily, causing false-positives, which can ruin results unexpectedly. Until you know them well, start simply, and test them every imaginable way. And, once you think you know them well, keep doing that; Patterns in code we write where I work are a particular hot-button for me, and I'm always finding holes in them in our code-reviews and requiring them to be tightened until they do exactly what the developer meant, not what they thought they meant.
While the pattern above works, I'd probably do it a bit differently in Ruby. Using the tools made for the job:
require 'uri'
URL = 'https://xxxxxx.cloudfront.net/qa/club/Slide1.PNG'
uri = URI.parse(URL)
path = uri.path # => "/qa/club/Slide1.PNG"
path.split('/')[1] # => "qa"
Or, more succinctly:
URI.parse(URL).path.split('/')[1] # => "qa"

How can I get wanted part from string with regular expression

I have a string like #'test'
and I have to get only test word without #' '
how can I match them with regular expression at javascript?

try the regex below:
#\'([^']*)\'
get group(1)
and if your language supports look-behind,( e.g. python, perl, java...):
(?<=#\')[^']*
should work too without grouping.
oh, just saw you edit your question, as far as I know, js doesn't support look-behind, then you could take the option 1.

var firsName= "#'test'"
var objName = firsName .replace('#', "'");
lastName=objName.replace(/[']/g,'');
I fixed it like that. I dont know is it best way or not. thanks for helping

Invalid regular expression in javascript

I'm trying to find out if a string contains css code with this expression:
var pattern = new RegExp('\s(?[a-zA-Z-]+)\s[:]{1}\s*(?[a-zA-Z0-9\s.#]+)[;]{1}');
But I get "invalid regular expression" error on the line above...
What's wrong with it?
found the regex here: http://www.catswhocode.com/blog/10-regular-expressions-for-efficient-web-development
It's for PHP but it should work in javascript too, right?

What are the ? at the start of the two [a-zA-z-] blocks for? They look wrong to me.
The ? is unfortunately somewhat overload in regexp syntax, it can have three different meanings that I know of, and none of them match what I see in your example.
Also, your \s sequences need the backslash escaping because this is a string - they should look like \\s. To avoid escaping, just use the /.../ syntax instead of new Regexp("...").
That said, even that is insufficient - the regexp still produces an Invalid Group error in Chrome, probably related to the {1} sequences.

The ?'s are messing it up. I'm not sure what they are for.
/\s[a-zA-Z\-]+\s*:\s*[a-zA-Z0-9\s.#]+;/
worked for me (as far as compiling. I didn't test to see if it properly detected a CSS string).

Replace the quotes with / (slashes):
var pattern = /\s([a-zA-Z-]+)\s[:]{1}\s*([a-zA-Z0-9\s.#]+)[;]{1}/;
You also don't need the new RegExp() part either, which is why it's been removed; instead of using a quote or double quote to denote a string, JavaScript uses a slash / to denote a regular expression, which isn't a normal string.

That regular expression is very bad and I would avoid its source in the future. That said, I cleaned it up a bit and got the following result:
var pattern = /\s(?:[a-zA-Z-]+)\s*:\s*(?:[^;\n\r]+);/;
this matches something that looks like css, for example:
background-color: red;
Here's the fiddle to prove it, though I'd recommend to find a different solution to your problem. This is a very simple regex and it's not save to say that it is reliable.

URL regex does not work in javascript

I am trying to use John Gruber's URL regex in Javascript but NetBeans keeps telling me there is a syntax error and illegal errors:
var patt = "/(?i)\b((?:[a-z][\w-]+:(?:/{1,3}|[a-z0-9%])
|www\d{0,3}[.]|[a-z0-9.\-]+[.][a-z]
{2,4}/)(?:[^\s()<>]+|\(([^\s()<>]+|
(\([^\s()<>]+\)))*\))+(?:\(([^\s()<>]+|
(\([^\s()<>]+\)))*\)|[^\s`!()\[\]{};:
'".,<>?«»“”‘’]))/";
Anyone know how to solve this?

As others have said, it's the double quote. But alternatively, you can just write the regexp as a literal in javascript (but then you need to escape the forward slashes in lines 1 and 3 instead).
var regexp = /\b((?:[a-z][\w-]+:(?:\/{1,3}|[a-z0-9%])|www\d{0,3}[.]|[a-z0-9.\-]+[.][a-z]{2,4}\/)(?:[^\s()<>]+|\(([^\s()<>]+|(\([^\s()<>]+\)))*\))+(?:\(([^\s()<>]+|(\([^\s()<>]+\)))*\)|[^\s`!()\[\]{};:'".,<>?«»“”‘’]))/i;
I also moved the case-insensitive modifier to the end. Just because. (edit: Well, not just "because" - see Alan Moore's comment below)
Note: Whether you use a literal or a string, it has to be on 1 line.

put the whole expression in one line, and remove the quotes at the start and end so it looks like this var patt = /the-long-patttern/;, netbeans will still complain, but the browsers won't and thats what matters.

You should write it like this in NetBeans:
"(?i)\\b((?:[a-z][\\w-]+:(?:\\/{1,3}|[a-z0-9%])|www\\d{0,3}[.]|[a-z0-9.\\-]"
+ "+[.][a-z]{2,4}\\/)(?:[^\\s()<>]+|\\(([^\\s()<>]+|(\\([^\\s()<>]+\\)))*\\))"
+ "+(?:\\(([^\\s()<>]+|(\\([^\\s()<>]+\\)))*\\)|[^\\s`!()\\[\\]{};:'\".,<>?«»“”‘’]))";