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Replacing only exact matches in Regex [duplicate]

This question already has answers here:
How can I match a whole word in JavaScript?
(4 answers)
Closed 4 months ago.
I have a javascript function that replaces strings that match against a profanity library with symbols.
eg. damn is transformed into ##$%&!
However, this replace is non-discriminating, and will transform partial matches as well.
eg. classic is transformed into cl##$%&!ic
I'm very new to TS/JS and Regex and would like some help understanding this function's arguments and how to modify them for only exact matches.
this.replace(new RegExp(str1.replace(/([\/\,\!\\\^\$\{\}\[\]\(\)\.\*\+\?\|\<\>\-\&])/g, "\\$&"), (ignore ? "gi" : "g")), (typeof (str2) == "string") ? str2.replace(/\$/g, "$$$$") : str2);

To avoid partial matches, the normal solution is to surround what you want to match with word boundaries \b.
The following example assumes that profanities does not contain any words that contain regex special characters.
Notice that the "shit" in "mishit" and the "ass" in "class" do not get replaced.
const profanities = ['damn', 'shit', 'ass'];
// As regex literal: /\b(?:damn|shit|ass)\b/
const re = new RegExp('\\b(?:' + profanities.join('|') + ')\\b', 'gi');
const text = "Damn, another mishit. I am shit at pool. Time to get my ass to class.";
console.log(text.replace(re, '##$%&!'));

String starting with backslash hacks my regex [duplicate]

This question already has answers here:
How can I use backslashes (\) in a string?
(4 answers)
Closed 3 years ago.
My string should be in the IRC command format : "/add john".
So, i created this Regex :
var regex = /^\/add ([A-Za-z0-9]+)$/
var bool = regex.test('\/add user1');
alert(bool);
The problem is either I use /***/ or RegExp syntax, if I set a backslash at the beginning of my string (like in my example above), my alert pop up show "true" and I don't want that.
I code in Javascript

You can use String.raw to make sure that the backlash is not removed when testing your input:
var regex = /^\/add ([A-Za-z0-9]+)$/
var bool = regex.test(String.raw`\/add user1`);
alert(bool);
You can play with this code here: https://jsbin.com/ziqecux/25/edit?js

How do remove all Unicode from string, BUT keep lanauges such as: Japanese, Greek, Hindi etc [duplicate]

This question already has answers here:
How can I use Unicode-aware regular expressions in JavaScript?
(11 answers)
Closed 4 years ago.
How would I remove all Unicode from this string【Hello!】★ ああああ
I need to remove all the "weird" symbols (【, ★, 】) and keep "Hello!" and "ああああ". This needs to work for all languages not just Japanese.

You want to remove characters within the Unicode categories Other Symbol, Combining Symbol, and Enclosing Mark, but leave those from other categories.
Using regular expressions, those match the classes \p{So}, \p{Sk} and \p{Me}, respectively. You might for example use XRegExp.replace().

I have found a solution. Using XRegEXP, I was able to use PHP's \p{Common} in node.
const xreg = require('xregexp');
let str = '【Hello!】★ ああああ】';
let regex = new xreg('\\p{Common}', 'g');
let res = xreg.replace(str, regex, ' ');
console.log(res); // Hello ああああ

How do I insert something at a specific character with Regex in Javascript [duplicate]

This question already has answers here:
Simple javascript find and replace
(6 answers)
Closed 5 years ago.
I have string "foo?bar" and I want to insert "baz" at the ?. This ? may not always be at the 3 index, so I always want to insert something string at this ? char to get "foo?bazbar"

The String.protype.replace method is perfect for this.
Example
let result = "foo?bar".replace(/\?/, '?baz');
alert(result);
I have used a RegEx in this example as requested, although you could do it without RegEx too.
Additional notes.
If you expect the string "foo?bar?boo" to result in "foo?bazbar?boo" the above code works as-is
If you expect the string "foo?bar?boo" to result in "foo?bazbar?bazboo" you can change the call to .replace(/\?/g, '?baz')

You don't need a regular expression, since you're not matching a pattern, just ordinary string replacement.
string = 'foo?bar';
newString = string.replace('?', '?baz');
console.log(newString);

How to use dynamic variable between regular expression [duplicate]

This question already has answers here:
How do you use a variable in a regular expression?
(27 answers)
Closed 6 years ago.
I have string which contains some date and some comma separated values like this
var a = "1,13,20160308,200500000012016,10,Pending,01-02-2016,1|#|1,13,20160418,200500000012016,10,Pending,08-03-2016,1|#|1,13,20160623,200500000012016,10,Pending,18-04-2016,1|#|1,13,20160803,200500000012016,10,Pending,23-06-2016,1|#|1,13,20160912,200500000012016,10,Pending,03-08-2016,1|#|1,13,20161022,200500000012016,10,Pending,12-09-2016,1|#|1,13,20161129,200500000012016,10,Pending,22-10-2016,1|#|1,13,20170110,200500000012016,10,Pending,29-11-2016,1|#|1,13,20170215,200500000012016,10,Pending,10-01-2017,1|#|15-02-2017 APPEARANCE"
regular expression: /(.)*?01-02-2016(.)*?\|\#\|/igm
By using this regular expression i can able to delete unnecessary part in string.
Now i want to change 03-08-3016 (date) dynamically. If i use
var date = "01-02-2016"
var reg = /(.)*?${date}(.)*?\|\#\|/igm;
If you pring reg in console.log you will get like this below
console.log(reg) ----> output: '/(.)?01-02-2016(.)?|#|/igm'
Expected Final output will delete upto 01-02-2016,1|#|

Use this.
var regex="(.)*?01-02-2016(.)*?\\|\\#\\|";
var rx=new RegExp(regex,"igm");
console.log(rx);
//Then when do you want to change,
regex=regex.replace("01-02-2016","03-02-2016");
rx=new RegExp(regex,"igm");
console.log(rx);
JavaScript have 2 methods to make a Regular Expression.
1. write it in slashes //
2. Make from string using new RexExp(string);
If you make it from string, you can give the constraint(" global, incase, etc.") as the second parameter as i did in the above.
and also you have to double escape (\) the escape characters.