We Keep Coding

regex encapsulation

I've got a question concerning regex.
I was wondering how one could replace an encapsulated text, something like {key:23} to something like <span class="highlightable">23</span, so that the entity will still remain encapsulated, but with something else.
I will do this in JS, but the regex is what is important, I have been searching for a while, probably searching for the wrong terms, I should probably learn more about regex, generally.
In any case, is there someone who knows how to perform this operation with simplicity?
Thanks!

It's important that you find {key:23} in your text first, and then replace it with your wanted syntax, this way you avoid replacing {key:'sometext'} with that syntax which is unwanted.
var str = "some random text {key:23} some random text {key:name}";
var n = str.replace(/\{key:[\d]+\}/gi, function myFunction(x){return x.replace(/\{key:/,'<span>').replace(/\}/, '</span>');});
this way only {key:AnyNumber} gets replaced, and {key:AnyThingOtherThanNumbers} don't get touched.

It seems you are new to regex. You need to learn more about character classes and capturing groups and backreferences.
The regex is somewhat basic in your case if you do not need any nested encapsulated text support.
Let's start:
The beginning is {key: - it will match the substring literally. Note that { can be a special character (denoting start of a limiting quantifier), thus, it is a good idea to escape it: {key:.
([^}]+) - This is a bit more interesting: the round brackets around are a capturing group that let us later back-reference the matched text. The [^}]+ means 1 or more characters (due to +) other than } (as [^}] is a negated character class where ^ means not)
} matches a } literally.
In the replacement string, we'll get the captured text using a backreference $1.
So, the entire regex will look like:
{key:([^}]+)}
See demo on regex101.com
Code snippet:
var re = /{key:([^}]+)}/g;
var str = '{key:23}';
var subst = '<span class="highlightable">$1</span>';
document.getElementById("res").innerHTML = str.replace(re, subst);
.highlightable
{
color: red;
}
<div id="res"/>
If you want to use a different behavior based on the value of key, then you'll need to adjust the regex to either match digits only (with \d+) or letters only (say, with [a-zA-Z] for English), or other shorthand classes, ranges (= character classes), or their combinations.

If your string is in var a, then:
var test = a.replace( /\{key:(\d+)\}/g, "<span class='highlightable'>$1</span>");

Regex trying to match characters before and after symbol

I'm trying to match characters before and after a symbol, in a string.
string: budgets-closed
To match the characters before the sign -, I do: ^[a-z]+
And to match the other characters, I try: \-(\w+) but, the problem is that my result is: -closed instead of closed.
Any ideas, how to fix it?
Update
This is the piece of code, where I was trying to apply the regex http://jsfiddle.net/trDFh/1/
I repeat: It's not that I don't want to use split; it's just I was really curious, and wanted to see, how can it be done the regex way. Hacking into things spirit
Update2
Well, using substring is a solution as well: http://jsfiddle.net/trDFh/2/ and is the one I chosed to use, since the if in question, is actually an else if in a more complex if syntax, and the chosen solutions seems to be the most fitted for now.

Use exec():
var result=/([^-]+)-([^-]+)/.exec(string);
result is an array, with result[1] being the first captured string and result[2] being the second captured string.
Live demo: http://jsfiddle.net/Pqntk/

I think you'll have to match that. You can use grouping to get what you need, though.
var str = 'budgets-closed';
var matches = str.match( /([a-z]+)-([a-z]+)/ );
var before = matches[1];
var after = matches[2];
For that specific string, you could also use
var str = 'budgets-closed';
var before = str.match( /^\b[a-z]+/ )[0];
var after = str.match( /\b[a-z]+$/ )[0];
I'm sure there are better ways, but the above methods do work.

If the symbol is specifically -, then this should work:
\b([^-]+)-([^-]+)\b
You match a boundry, any "not -" characters, a - and then more "not -" characters until the next word boundry.
Also, there is no need to escape a hyphen, it only holds special properties when between two other characters inside a character class.
edit: And here is a jsfiddle that demonstrates it does work.

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,"");

Replacing commas in resultset with new line in jQuery

I have not had to do something like this in the past and am wondering if it is indeed possible. I am allowing multiple code numbers to be added in an so long as they are delimited by commas. What I am wanting to do is upon the user clicking on the "okay" button that a showing the numbers entered will show them one on top of each other with a "delete" button next to them. That part is easy...the hard part is getting the comma stripped out and the new line placed in its stead.
Are there any examples or samples that anyone can point me too?

You'd use String#replace with a regular expression using the g flag ("global") for the "search" part, and a replacement string of your choosing (from your question, I'm not sure whether you want <br> — e.g., an HTML line break — or \n which really is a newline [but remember newlines are treated like spaces in HTML]). E.g.:
var numbers = "1,2,3,4,5,6";
numbers = numbers.replace(/,/g, '<br>'); // Or \n, depending on your needs
Or if you want to allow for spaces, you'd put optional spaces either side of the comma in the regex:
var numbers = "1,2,3,4,5,6";
numbers = numbers.replace(/ *, */g, '<br>'); // Or \n, depending on your needs

To replace all occurrences of a string you need to use a regexp with the g (global) modifier:
var numlist = "1,4,6,7,3,34,34,634,34";
var numlistNewLine = numlist.replace(/,/g, '\n');
Alternatively, use .split() and .join()
var newList = numList.split(',').join('\n');

var numlist = "1,4,6,7,3,34,34,634,34";
var numlistNewLine = numlist.replace(',','\n');
No jQuery needed. String has a nice replace() function for you.

Split string in JavaScript using a regular expression

I'm trying to write a regex for use in javascript.
var script = "function onclick() {loadArea('areaog_og_group_og_consumedservice', '\x26roleOrd\x3d1');}";
var match = new RegExp("'[^']*(\\.[^']*)*'").exec(script);
I would like split to contain two elements:
match[0] == "'areaog_og_group_og_consumedservice'";
match[1] == "'\x26roleOrd\x3d1'";
This regex matches correctly when testing it at gskinner.com/RegExr/ but it does not work in my Javascript. This issue can be replicated by testing ir here http://www.regextester.com/.
I need the solution to work with Internet Explorer 6 and above.
Can any regex guru's help?

Judging by your regex, it looks like you're trying to match a single-quoted string that may contain escaped quotes. The correct form of that regex is:
'[^'\\]*(?:\\.[^'\\]*)*'
(If you don't need to allow for escaped quotes, /'[^']*'/ is all you need.) You also have to set the g flag if you want to get both strings. Here's the regex in its regex-literal form:
/'[^'\\]*(?:\\.[^'\\]*)*'/g
If you use the RegExp constructor instead of a regex literal, you have to double-escape the backslashes: once for the string literal and once for the regex. You also have to pass the flags (g, i, m) as a separate parameter:
var rgx = new RegExp("'[^'\\\\]*(?:\\\\.[^'\\\\]*)*'", "g");
while (result = rgx.exec(script))
print(result[0]);

The regex you're looking for is .*?('[^']*')\s*,\s*('[^']*'). The catch here is that, as usual, match[0] is the entire matched text (this is very normal) so it's not particularly useful to you. match[1] and match[2] are the two matches you're looking for.
var script = "function onclick() {loadArea('areaog_og_group_og_consumedservice', '\x26roleOrd\x3d1');}";
var parameters = /.*?('[^']*')\s*,\s*('[^']*')/.exec(script);
alert("you've done: loadArea("+parameters[1]+", "+parameters[2]+");");
The only issue I have with this is that it's somewhat inflexible. You might want to spend a little time to match function calls with 2 or 3 parameters?
EDIT
In response to you're request, here is the regex to match 1,2,3,...,n parameters. If you notice, I used a non-capturing group (the (?: ) part) to find many instances of the comma followed by the second parameter.
/.*?('[^']*')(?:\s*,\s*('[^']*'))*/

Maybe this:
'([^']*)'\s*,\s*'([^']*)'