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regex for capturing the values

need some help with nested double quotes regex,
I have the following string:
"abcd-1234\":" : value\":1234\":
and I want to capture the entire string and separate it out into key and value pair but I am not able to come with a proper regex.
Basically, I have the following string format -->
"key" : "value"
and I want to find a proper regex for the string format.
I am able capture the key and value individually with the following regex -->
((^[\"]).*\2(?![^:]))
But not able to get a proper regex for the entire string.
Please, can someone help me with the regex.

Imagine the following string: "\\" - That contains \" but is still a complete, valid string. You can't just 'ignore \" - you have to count backslashes.
(?:[^"\\]|\\.) will cover any 'in-the-string' character: Either a backslash followed by anything (. is anything), or any character at all, as long as it isn't either a backslash, or a quote. A string is a quote, followed by any amount of those, followed by a quote, thus, a regexp appears.
However, regexps probably aren't the right tool for the job. This looks like a part of a JSON formatted input; there are JSON parsers that do a much better job on this, covering far more cases.

How to Escape the unescaped double quotes in a CSV string in Node

This is very similar to
Regular expression to find unescaped double quotes in CSV file
However, the solutions presented don't work with Node.js's regex engine. Given a CSV string where columns are quoted with double quotes, but some columns have unescaped double quotes in them, what regex could be used to match these unescaped quotes and just remove them.
Example rows
"123","","SDFDS SDFSDF EEE "S"","asdfas","b","lll"
"123","","SDFDS SDFSDF EEE "S"","asdfas","b","lll"
So the two double quotes surrounding the S in the third column would get matched and removed. Needs to work in Node.js (14.16.1)
I have tried (?m)""(?![ \t]*(,|$)) but get a Invalid regular expression: /(?m)""(?![ \t]*(,|$))/: Invalid group exception

I don't know much about node.js, but assuming it is like the JavaScript flavor of regex then I have the following comments about the example you took from the prior answer:
I think your example is choking on the first element, (?m) which is unsupported in Javascript. However, that part is not essential to your task. It only turns on multiline processing and you don't need that if you feed the regex engine each line individually. If you find you still want to feed it a multiline string, then you can still turn on multiline in JavaScript - you do it with the "m" flag after the final delimiter, "/myregex/m". All of the other elements, including the negative lookahead are supported by JavaScript and probably by your engine as well. So, drop the (?m) part of your expression and try it again.
Even after you get it to work, the example row you provided will not be parsed according to your expectations by the sample regular expression. Its function is to identify all occurrences of two double-quotes that are not followed by a comma (or end of string). The ONLY two occurrences of doubled quotes in your example each have a comma after, so you will get no matches on this regex in your example.
It seems like you want some context-sensitive scanning to match and remove the inner pairs of double quotes while leaving the outer ones in place and handling commas inside your strings and possibly correctly quoted double quotes. Regular expression engines are really bad at this kind of processing and I don't think you are going to get satisfactory results whatever you come up with.
You can get an approximate solution to your problem by using regex once to parse the individual elements of the .csv stripping the outer quotes as you go and then running a second regex against each parsed element to either remove single occurrences of double quote or adding a second double-quote, where necessary. Then you can reassemble the string under program control.
This still will break if someone embeds a "", sequence in a data field string, so it's not perfect but it might be good enough for you.
The regex for splitting the .csv and stripping the double quotes is:
/(("(.*?)")|([^,]*))(,|$)/gm
This will accept either a "anything", OR a anything, repeatedly until the source is exhausted. Because of the capturing groups, the parsed text will either by in $3 (if the field was quoted) or $4 (if it was not quoted) but not both.
Here's a regexpReplace of your string with $3&$4 and a semicolon after each iteration (I took the liberty of adding a numeric field without the quotes so you could see that it handles both cases):
"123","","SDFDS SDFSDF EEE "S"",456,"asdfas","b","lll"
RegexpReplace(<above>,"((""(.*?)"")|([^,]*))(,|$)","$3$4;")
=> 123;;SDFDS SDFSDF EEE "S";456;asdfas;b;lll;;
See how the outer quotes have been stripped away. Now it's a simple thing to go through all the matches to remove all the remaining quotes, and then you can reconstruct the string from the array of matches.

Regexp in the Case of Single and Double Quotes

I have the following JavaScript:
let strTest = `
"The issue": "L'oggetto ",
"issue": "oggetto",
"issue": 'oggetto "novo" ',
`;
I'm trying to tokenize a string like the one above.
My regexp attempt:
let regExp = /["'](.*?)["']\s*?:\s*?['"](.*?)["']/gm;
This works fine, except in the case where I have a pair of single quotes (') inside of double quotes (") or vice-versa.
Is this possible with only one regular expression?

I answer my self , I think I came with a smaller regex:
` /["'](.*)["']\s*?:\s*?["'[](.*)["']]/g `
Have a look at regex101.com/r/g9WCbi/1

You can use backreferences:
/(["'])(.*?)\1\s*?:\s*?(['"])(.*?)\3/gm
This will include the quotes, in the tokenized string, but you can then remove them from the produced match by taking only the even numbered tokens.
Edit:
As #TJ Crowder points out, this will not work correctly if the string contains escaped quotes in the form of \" within the string. In order to completely accommodate those escaped quotes and not break on strings like \\"(an escaped backslash preceding a quote) you will need to parse with multiple regexes or take a different tactic
The other thing you might want to look at, if this is coming from JSON, is ignoring regex, and just iterating through the properties of your json object. It depends if the string you're getting is coming in as valid json or not.

Regex not working as expected in JavaScript

I wrote the following regex:
(https?:\/\/)?([da-z\.-]+)\.([a-z]{2,6})(\/(\w|-)*)*\/?
Its behaviour can be seen here: http://gskinner.com/RegExr/?34b8m
I wrote the following JavaScript code:
var urlexp = new RegExp(
'^(https?:\/\/)?([da-z\.-]+)\.([a-z]{2,6})(\/(\w|-)*)*\/?$', 'gi'
);
document.write(urlexp.test("blaaa"))
And it returns true even though the regex was supposed to not allow single words as valid.
What am I doing wrong?

Your problem is that JavaScript is viewing all your escape sequences as escapes for the string. So your regex goes to memory looking like this:
^(https?://)?([da-z.-]+).([a-z]{2,6})(/(w|-)*)*/?$
Which you may notice causes a problem in the middle when what you thought was a literal period turns into a regular expressions wildcard. You can solve this in a couple ways. Using the forward slash regular expression syntax JavaScript provides:
var urlexp = /^(https?:\/\/)?([da-z\.-]+)\.([a-z]{2,6})(\/(\w|-)*)*\/?$/gi
Or by escaping your backslashes (and not your forward slashes, as you had been doing - that's exclusively for when you're using /regex/mod notation, just like you don't have to escape your single quotes in a double quoted string and vice versa):
var urlexp = new RegExp('^(https?://)?([da-z.-]+)\\.([a-z]{2,6})(/(\\w|-)*)*/?$', 'gi')
Please note the double backslash before the w - also necessary for matching word characters.
A couple notes on your regular expression itself:
[da-z.-]
d is contained in the a-z range. Unless you meant \d? In that case, the slash is important.
(/(\w|-)*)*/?
My own misgivings about the nested Kleene stars aside, you can whittle that alternation down into a character class, and drop the terminating /? entirely, as a trailing slash will be match by the group as you've given it. I'd rewrite as:
(/[\w-]*)*
Though, maybe you'd just like to catch non space characters?
(/[^/\s]*)*
Anyway, modified this way your regular expression winds up looking more like:
^(https?://)?([\da-z.-]+)\.([a-z]{2,6})(/[\w-]*)*$
Remember, if you're going to use string notation: Double EVERY backslash. If you're going to use native /regex/mod notation (which I highly recommend), escape your forward slashes.

RegExp in JavaScript, when a quantifier is part of the pattern

I have been trying to use a regexp that matches any text that is between a caret, less than and a greater than, caret.
So it would look like: ^< THE TEXT I WANT SELECTED >^
I have tried something like this, but it isn't working: ^<(.*?)>^
I'm assuming this is possible, right? I think the reason I have been having such a tough time is because the caret serves as a quantifier. Thanks for any help I get!
Update
Just so everyone knows, they following from am not i am worked
/\^<(.*?)>\^/
But, it turned out that I was getting html entities since I was getting my string by using the .innerHTML property. In other words,
> ... >
< ... <
To solve this, my regexp actually looks like this:
\^<(.*?)((.|\n)*)>\^
This includes the fact that the string in between should be any character or new line. Thanks!

You need to escape the ^ symbol since it has special meaning in a JavaScript regex.
/\^<(.*?)>\^/
In a JavaScript regex, the ^ means beginning of the string, unless the m modifier was used, in which case it means beginning of the line.

This should work:
\^<(.*?)>\^
In a regex, if you want to use a character that has a special meaning (caret, brackets, pipe, ...), you have to escape it using a backslash. For example, (\w\b)*\w\. will select a sequence of words terminated by a dot.
Careful!
If you have to pass the regex pattern as a string, i.e. there's no regex literal like in javascript or perl, you may have to use a double backslash, which the programming language will escape to a single one, which will then be processed by the regex engine.
Same regex in multiple languages:
Python:
import re
myRegex=re.compile(r"\^<(.*?)>\^") # The r before the string prevents backslash escaping
PHP:
$result=preg_match("/\\^<(.*?)>\\^/",$subject); // Notice the double backslashes here?
JavaScript:
var myRegex=/\^<(.*?)>\^/,
subject="^<blah example>^";
subject.match(myRegex);
If you tell us what programming language you're writing in, we'll be able to give you some finished code to work with.
Edit: Whoops, didn't even notice this was tagged as javascript. Then, you don't have to worry about double backslash at all.
Edit 2: \b represent a word boundary. Though I agree yours is what I would have used myself.