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Get substring between substring and first occurrence of another string

I have URL pathnames that look similar to this: /service-area/i-need-this/but-not-this/. The /service-area/ part never changes, and the rest of the path is dynamic.
I need to get the part of the URL saying i-need-this.
Here was my attempt:
location.pathname.match(new RegExp('/service-area/' + "(.*)" + '/'));.
The goal was to get everything between /service-area/ and / but it's actually going up to the last occurrence of /, not the first occurrance. So the output from this is actually i-need-this/but-not-this.
I'm not so good with regex, is there a way it can be tweaked to get the desired result?

You need a lazy regex rather than a greedy one - so (.*?) instead of (.*). See also: What do 'lazy' and 'greedy' mean in the context of regular expressions?

You can do this without a regex too using replace and split:
var path = '/service-area/i-need-this/but-not-this/';
var res = path.replace('/service-area/', '').split('/')[0];
console.log(res);

Regex to detect urls with '?' character at the end

I found many solutions, but none was useful for me.
Let's say, as an example, I want to find URLs that start with www. and end with a space or ?. In this case, I really mean it ends in a ?, not that it's necessarily a CGI-related URL.
I'm trying to use the regex
var r = /(^|[\s\?])(www\..+?(?=([\s]|\?|($))))/g;
My sample use: http://jsfiddle.net/DKNat/2/
How can I use \? in a regex to prevent the end of the URL containing / before ??
http://jsfiddle.net/DKNat/11/
I can't solve last prob with DOT at the end of url.
Can any body help?

Try this in your fiddle:
var r = /(^|\??)(www\.[^\?]+)/g;
I updated your fiddle here:
http://jsfiddle.net/DKNat/3/
Update:
I see what you are trying to do now. Unfortunately, both your strings are essentially the same, apart from the /, so unless you want your regex to make the assumption that a ? anywhere after a slash denotes a CGI call, then there isn't much you can do. But you could try this:
var r = /(^|\??)(www\.[^\?]+\/[^\/]+\?[^\?]+|www\.[^\?]+)/g;
Updated fiddle:
http://jsfiddle.net/DKNat/5/
Update 2: After determining the requirements, this is the final RegExp I added to fiddle 10:
var r = /(^|[\?\s])(www\.[^\? ]+\/[^\/ ]*\?[^\? ]+|www\.[^\? ]+)/g;

what's wrong with this regular expression? getting the hash part of an url

I´m trying to get the first part of a hash from a url (the part between the # and a /, a ? or the end of the string
So far now I came out with this:
r = /#(.*)[\?|\/|$]/
// OK
r.exec('http://localhost/item.html#hash/sub')
["#hash/", "hash"]
// OK
r.exec('http://localhost/item.html#hash?sub')
["#hash?", "hash"]
// WAT?
r.exec('http://localhost/item.html#hash')
null
I was expeting to receive "hash"
I tracked down the problem to
/#(.*)[$]/
r2.exec('http://localhost/item.html#hash')
null
any idea what could be wrong?

r = /#(.*)[\?|\/|$]/
When $ appears in [] (character class, it's the literal "$" character, not the end of input/line. In fact, your [\?|\/|$] part is equivalent to just [?/$|], which matches the 4 specific characters (including pipe).
Use this instead (JSFiddle)
r = /#(.+?)(\?|\/|$)/

You aren't supposed to write [$] (within a character class) unless you want to match the $ literally and not the end of line.
/#(.*)$/
Code:
var regex = /\#(.*)$/;
regex.exec('http://localhost/item.html#hash');
Output:
["#hash", "hash"]
Your regex: /#(.*)[\?|\/|$]/
//<problem>-----^ ^-----<problem>
| operator won't work within [], but within ()
$ will be treated literally within []
.* will match as much as possible. .*? will be non-greedy
On making the above changes,
you end up with /#(.*?)(\?|\/|$)/

I use http://regexpal.com/ to test my regular expressions.
Your problem here is that your regular expression wants a /. So it don't works with http://localhost/item.html#hash but it works with http://localhost/item.html#hash/
Try this one :
r = /#([^\?|\/|$]*)/

You can't use the $ end-of-string marker in a character class. You're probably better off just matching characaters that aren't / or ?, like this:
/#([^\?\/]*)/

Why Regex? Do it like this (nearly no regex):
var a = document.createElement('a');
a.href = 'http://localhost/item.html#hash/foo?bar';
console.log(a.hash.split(/[\/\?]/)[0]); // #hash
Just for the sake, if it is node.js you are working with:
var hash = require('url').parse('http://localhost/item.html#hash').hash;

I found this regular expression that seems to work
r = /#([^\/\?]*)/
r.exec('http://localhost/item.html#hash/sub')
["#hash", "hash"]
r.exec('http://localhost/item.html#hash?sub')
["#hash", "hash"]
r.exec('http://localhost/item.html#hash')
["#hash", "hash"]
Anyway, I still don't get why the original one isn't working

Javascript regex expression to replace multiple strings?

I've a string done like this: "http://something.org/dom/My_happy_dog_%28is%29cool!"
How can I remove all the initial domain, the multiple underscore and the percentage stuff?
For now I'm just doing some multiple replace, like
str = str.replace("http://something.org/dom/","");
str = str.replace("_%28"," ");
and go on, but it's really ugly.. any help?
Thanks!
EDIT:
the exact input would be "My happy dog is cool!" so I would like to get rid of the initial address and remove the underscores and percentage and put the spaces in the right place!
The problem is that trying to put a regex on Chrome "something goes wrong". Is it a problem of Chrome or my regex?

I'd suggest:
var str = "http://something.org/dom/My_happy_dog_%28is%29cool!";
str.substring(str.lastIndexOf('/')+1).replace(/(_)|(%\d{2,})/g,' ');
JS Fiddle demo.
The reason I took this approach is that RegEx is fairly expensive, and is often tricky to fine tune to the point where edge-cases become less troublesome; so I opted to use simple string manipulation to reduce the RegEx work.
Effectively the above creates a substring of the given str variable, from the index point of the lastIndexOf('/') (which does exactly what you'd expect) and adding 1 to that so the substring is from the point after the / not before it.
The regex: (_) matches the underscores, the | just serves as an or operator and the (%\d{2,}) serves to match digit characters that occur twice in succession and follow a % sign.
The parentheses surrounding each part of the regex around the |, serve to identify matching groups, which are used to identify what parts should be replaced by the ' ' (single-space) string in the second of the arguments passed to replace().
References:
lastIndexOf().
replace().
substring().

You can use unescape to decode the percentages:
str = unescape("http://something.org/dom/My_happy_dog_%28is%29cool!")
str = str.replace("http://something.org/dom/","");

Maybe you could use a regular expression to pull out what you need, rather than getting rid of what you don't want. What is it you are trying to keep?
You can also chain them together as in:
str.replace("http://something.org/dom/", "").replace("something else", "");

You haven't defined the problem very exactly. To get rid of all stretches of characters ending in %<digit><digit> you'd say
var re = /.*%\d\d/g;
var str = str.replace(re, "");

ok, if you want to replace all that stuff I think that you would need something like this:
/(http:\/\/.*\.[a-z]{3}\/.*\/)|(\%[a-z0-9][a-z0-9])|_/g
test
var string = "http://something.org/dom/My_happy_dog_%28is%29cool!";
string = string.replace(/(http:\/\/.*\.[a-z]{3}\/.*\/)|(\%[a-z0-9][a-z0-9])|_/g,"");

Remove part an ever-changing text string with javascript?

I have a string of text "AB-123-2011-07-09", and need to remove everything except "123", then add a "#" sign to the end result.
The string "123" is ever increasing in number, as is the "2011-07-09" (a date). Only "AB" stays the same.
So the end result would be: #123
Is this possible?
Thanks.
EDIT: Just to clarify, I was needing a script that could globally search a page and replace any text which had the format of "AB-xxx-xxxx-xx-xx" with just the digits highlighted here in bold, then adding the "#" before it.
Currently there are only 3 digits in that position, but in the future there may be four.
My code:
function Replace() {
var OldString = "AB-123-2011-07-09";
var NewString = OldString.replace(/^AB-(\d+)-.*/, "#$1");
document.body.innerHTML = document.body.innerHTML.replace(OldString, NewString);
}
window.onload = Replace();
So far it only replaces 1 instance of the string, and uses a fixed string ("AB-123-2011-07-09").
What regular expression do I need to make the 'OldString' dynamic, rather than it being fixed as it is now?

var data = "AB-123-2011-07-09";
var field = data.split('-')[1];
document.write("#" + field);
http://jsfiddle.net/efortis/8acDr/

The following regex would work, but in this case I don't think you need a regex at all (as #Eric has already shown).
"AB-123-2011-07-09".replace(/^AB-(\d+)-.*/, "#$1");
This results in the value #123
http://jsfiddle.net/3XhbE/

Does this work?
var result = mystring.replace(new RegExp(AB-([0-9]+)-[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9], "g"),"#$1");
mystring is the "AB-123-2011-07-09" string and result would be "#123".

This is of course possible. This regex would do the trick:
“AB-123-2011-07-09“.replace(/^AB-(\d+)-\d+-\d+-\d+$/, “#$1“);
It also checks you given syntax and that there is nothing else in the string.
migg