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Javascript regex parse complex url string

I need to parse a complex URL string to fetch specific values.
From the following URL string:
/api/rss/feeds?url=http://any-feed-url-a.com?filter=hot&format=rss&url=http://any-feed-url-b.com?filter=rising&format=rss
I need to extract this result in array format:
['http://any-feed-url-a.com?filter=hot&format=rss', 'http://any-feed-url-b.com?filter=rising&format=rss']
I tried already with this one /url=([^&]+)/ but I can't capture all correctly all the query parameters. And I would like to omit the url=.
RegExr link
Thanks in advance.

This regex works for me: url=([a-z:/.?=-]+&[a-z=]+)
also, you can test this: /http(s)?://([a-z-.?=&])+&/g
const string = '/api/rss/feeds?url=http://any-feed-url.com?filter=hot&format=rss&url=http://any-feed-url.com?filter=latest&format=rss'
const string2 = '/api/rss/feeds?url=http://any-feed-url.com?filter=hot&format=rss&next=parm&url=http://any-feed-url.com?filter=latest&format=rss'
const regex = /url=([a-z:/.?=-]+&[a-z=]+)/g;
const regex2 = /http(s)?:\/\/([a-z-.?=&])+&/g;
console.log(string.match(regex))
console.log(string2.match(regex2))

have you tried to use split method ? instead of using regex.
const urlsArr = "/api/rss/feeds?url=http://any-feed-url-a.com?filter=hot&format=rss&url=http://any-feed-url-b.com?filter=rising&format=rss".split("url=");
urlsArr.shift(); // removing first item from array -> "/api/rss/feeds?"
console.log(urlsArr)
)
which is going to return ["/api/rss/feeds?", "http://any-feed-url-a.com?filter=hot&format=rss&", "http://any-feed-url-b.com?filter=rising&format=rss"] then i am dropping first item in array
if possible its better to use something else then regex CoddingHorror: regular-expressions-now-you-have-two-problems

You can matchAll the url's, then map the capture group 1 to an array.
str = '/api/rss/feeds?url=http://any-feed-url-a.com?filter=hot&format=rss&url=http://any-feed-url-b.com?filter=rising&format=rss'
arr = [...str.matchAll(/url=(.*?)(?=&url=|$)/g)].map(x => x[1])
console.log(arr)
But matchAll isn't supported by older browsers.
But looping an exec to fill an array works also.
str = '/api/rss/feeds?url=http://any-feed-url-a.com?filter=hot&format=rss&url=http://any-feed-url-b.com?filter=rising&format=rss'
re = /url=(.*?)(?=&url=|$)/g;
arr = [];
while (m = re.exec(str)) {
arr.push(m[1]);
}
console.log(arr)

If your input is better-formed in reality than shown in the question and you’re targeting a modern JavaScript environment, there’s URL/URLSearchParams:
const input = '/api/rss/feeds?url=http://any-feed-url-a.com?filter=hot%26format=rss&url=http://any-feed-url-b.com?filter=rising%26format=rss';
const url = new URL(input, 'http://example.com/');
console.log(url.searchParams.getAll('url'));
Notice how & has to be escaped as %26 for it to make sense.
Without this input in a standard form, it’s not clear which rules of URLs are still on the table.

Dynamic string cutting

Okay, so I have a filepath with a variable prefix...
C:\Users\susan ivey\Documents\VKS Projects\secc-electron\src\views\main.jade
... now this path will be different for whatever computer I'm working on...
is there a way to traverse the string up to say 'secc-electron\', and drop it and everything before it while preserving the rest of it? I'm familiar with converting strings to arrays to manipulate elements contained within delimiters, but this is a problem that I have yet to come up with an answer to... would there be some sort of regex solution instead? I'm not that great with regex so I wouldn't know where to begin...

What you probably want is to do a split (with regex or not):
Here's an example:
var paragraph = 'C:\\Users\\susan ivey\\Documents\\VKS Projects\\secc-electron\\src\\views\\main.jade';
var splittedString = paragraph.split("secc-electron"); // returns an array of 2 element containing "C:\\Users\\susan ivey\\Documents\\VKS Projects\\" as the first element and "\\src\\views\\main.jade" as the 2nd element
console.log(splittedString[1]);
You can have a look at this https://www.w3schools.com/jsref/jsref_split.asp to learn more about this function.

With Regex you can do:
var myPath = 'C:\Users\susan ivey\Documents\VKS Projects\secc-electron\src\views\main.jade'
var relativePath = myPath.replace(/.*(?=secc-electron)/, '');
The Regex is:
.*(?=secc-electron)
It matches any characters up to 'secc-electron'. When calling replace it will return the last part of the path.

You can split the string at a certain point, then return the second part of the resulting array:
var string = "C:\Users\susan ivey\Documents\VKS Projects\secc-electron\src\views\main.jade"
console.log('string is: ', string)
var newArray = string.split("secc-electron")
console.log('newArray is: ', newArray)
console.log('newArray[1] is: ', newArray[1])

Alternatively you could use path.parse(path); https://nodejs.org/api/path.html#path_path_parse_path and retrieve the parts that you are interested in from the object that gets returned.

How to select part of the word using regular expression?

I have some text and i want to find all emails parts in it. Then return only domeins part, it should look something like:
meth#buisness.com --> buisness.com
yaourt#yoplait.fr --> oplait.fr
I tried to do this:
Code
var text = "I get a mail from meth#buisness.com (by the way I thought its domain was buisness.com), it was sent to yaourt#yoplait.fr, but the guys of gmail.com said we could only trust the yaourt#cesi.fr adress";
function getDomainsOfEmails(text) {
var regMatch = /#([a-z]+.[a-z]+)/g;
var regReturn = text.match(regMatch);
console.log( regReturn);
return regReturn;
}
getDomainsOfEmails(text);
But i don't know how to exclude an "#"sign from the search.

Parentheses in RegExp create cature group. The regexp.exec function returns an array where 0 is the whole match and then all other cells contain capture groups from left to right. So this:
var reg = /#([a-z0-9-]+\.[a-z]+)/ig;
reg.exec(text);
Will return the following on first call:
[
0: "#yoplait.fr"
1: "yoplait.fr"
]
And if you call it again, since the expression has a global flag, it'll get the next result:
[
0: "#buisness.com"
1: "buisness.com"
]

but best thing to divide this to two part and get the second part. try this i hope this is work
(?<=#)[^.]+(?=\.).*$

Check Array Entries with Regex

I have an Array with one or more entries. Each one is a string (List of urls in open Tabs via Firefox SDK). I want to check if a specific url is already opened in some of the tabs (nothing special till now).
My problem is, that the url in tab list can have four diffrent fourms. For example:
Url I want to find in the tablist:
https://cmsr-author.de/cf#/content/test/de.html
But the url can also look like this:
https://cmsr-author.de/content/test/de.html
https://cmsr-author.de/test/de.html
https://cmsr-author.de/cf#/test/de.html
Of course the last part of the url (after /test/...) is always something diffrent. If I wasn't able to find one of the four urls in the tablist i want to call some other action.
My Solution till now is to build some if-chain:
if (res !== url1) {
if (res !== url2) {
if ...
But i thought there must be some more elegant way. Maybe via RegEx? I already have a capture to catch the first part (which stays the same https://cmsr-author.ws...) with it four forms. But i dont know how to implent this probably.

var urls = ["https://cmsr-author.de/content/test/de.html","https://cmsr-author.de/test/de.html","https://cmsr-author.de/cf#/test/de.html"]
var filtered = urls.filter(function(url)
{
return url.indexOf("cf#") > -1 && url.endsWith("/test/de.html")
})
var contains = filtered.length > 0
console.log(contains)

If you want to use regex you can do this by using groups for the middle part, which is explained in detail here: http://www.regular-expressions.info/refcapture.html
Practically, your regex would look something like that:
https:\/\/cmsr-author\.de\/(content|...|...)\/de\.html
Where ... must be replaced by the middle parts of the url which differ.
Note that | is "or" used to provide multiple possibilities within the group. The character / and . must be escaped since they have special roles in regex.
I hope that helps!

My English is not good,Do not fully understand what you mean,According to my idea,You should need a regular expression,Only to match the first.If I am wrong,
please # me.
I hope that helps!
var reg = /^https:\/\/cmsr\-author\.de\/cf#\/(?:\w+\/)+test\/de\.html$/gi;
var str1 = "https://cmsr-author.de/cf#/content/test/de.html";
var str2 = "https://cmsr-author.de/content/test/de.html";
var str3 = "https://cmsr-author.de/test/de.html";
var str4 = "https://cmsr-author.de/cf#/test/de.html";
console.log(reg.test(str1));
console.log(reg.test(str2));
console.log(reg.test(str3));
console.log(reg.test(str4));

JS Regex match string with $

I am trying to write something that would look at tweets and pull up info about stocks being mentioned in the tweet. People use $ to reference stock symbols on twitter but I cant escape the $.
I also dont want to match any price mention or anything like that so basically match $AAPL and not $1500
I was thinking it would be something like this
\b\$[a-zA-Z].*\b
if there are multiple matches id like to loop through them somehow so something like
while ((tweet = reg.exec(sym_pat)) !== null) {
//replace text with stock data.
}
This expression gives me an unexpected illegal token error
var symbol_pat = new RegExp(\b\$[a-z]*);
Thanks for the help if you want to see the next issue I ran into
Javascript AJAX scope inside of $.each Scope

Okay, you've stated that you want to replace the matches with their actual stock values. So, you need to get all of the matching elements (stock ticker names) and then for each match you're going to replace the it with the stock value.
The answer will "read" very similarly to that sentence.
Assume there's a tweet variable that is the contents of a particular tweet you're going to work on:
tweet.match(/\b\$[A-Za-z]+\b/g).forEach(function(match) {
// match looks like '$AAPL'
var tickerValue = lookUpTickerValue(match);
tweet.replace(match, tickerValue);
});
This is assuming you have some logic somewhere that will grab the ticker value for the given stock name and then replace it (it should probably return the original value if it can't find a match, so you don't mangle lovely tweets like "Barbara Streisand is $ATAN").

var symbol_pat = new RegExp('\\b\\$[a-z]+\\b','gi');
// or
var symbol_pat = /\b\$[a-z]+\b/gi;
Also, for some reason JS can not calculate the beginning of a word by \b, it just catches the one at the end.
EDIT: If you're replacing the stock symbols you can use the basic replace method by a function and replace that data with predefined values:
var symbol_pat = /(^|\s)(\$[a-z]+\b)/gi;
var stocks = {AAPL:1,ETC:2}
var str = '$aapl ssd $a a$s$etc $etc';
console.log(str);
str = str.replace(symbol_pat, function() {
var stk = arguments[2].substr(1).toUpperCase();
// assuming you want to replace $etc as well as $ETC by using
// the .toUpperCase() method
if (!stocks[stk]) return arguments[0];
return arguments[0].replace(arguments[2],stocks[stk]);
});
console.log(str);