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Extract Twitter handlers from string using regex in JavaScript

I Would like to extract the Twitter handler names from a text string, using a regex. I believe I am almost there, except for the ">" that I am including in my output. How can I change my regex to be better, and drop the ">" from my output?
Here is an example of a text string value:
"PlaymakersZA, Absa, DiepslootMTB"
The desired output would be an array consisting of the following:
PlaymakersZA, Absa, DiepslootMTB
Here is an example of my regex:
var array = str.match(/>[a-z-_]+/ig)
Thank you!

You can use match groups in your regex to indicate the part you wish to extract.
I set up this JSFiddle to demonstrate.
Basically, you surround the part of the regex that you want to extract in parenthesis: />([a-z-_]+)/ig, save it as an object, and execute .exec() as long as there are still values. Using index 1 from the resulting array, you can find the first match group's result. Index 0 is the whole regex, and next indices would be subsequent match groups, if available.
var str = "PlaymakersZA, Absa, DiepslootMTB";
var regex = />([a-z-_]+)/ig
var array = regex.exec(str);
while (array != null) {
alert(array[1]);
array = regex.exec(str);
}

You could just strip all the HTML
var str = "PlaymakersZA, Absa, DiepslootMTB";
$handlers = str.replace(/<[^>]*>|\s/g,'').split(",");

RegExp to filter characters after the last dot

For example, I have a string "esolri.gbn43sh.earbnf", and I want to remove every character after the last dot(i.e. "esolri.gbn43sh"). How can I do so with regular expression?
I could of course use non-RegExp way to do it, for example:
"esolri.gbn43sh.earbnf".slice("esolri.gbn43sh.earbnf".lastIndexOf(".")+1);
But I want a regular expression.
I tried /\..*?/, but that remove the first dot instead.
I am using Javascript. Any help is much appreciated.

I would use standard js rather than regex for this one, as it will be easier for others to understand your code
var str = 'esolri.gbn43sh.earbnf'
console.log(
str.slice(str.lastIndexOf('.') + 1)
)

Pattern Matching
Match a dot followed by non-dots until the end of string
let re = /\.[^.]*$/;
Use this with String.prototype.replace to achieve the desired output
'foo.bar.baz'.replace(re, ''); // 'foo.bar'
Other choices
You may find it is more efficient to do a simple substring search for the last . and then use a string slicing method on this index.
let str = 'foo.bar.baz',
i = str.lastIndexOf('.');
if (i !== -1) // i = -1 means no match
str = str.slice(0, i); // "foo.bar"

Javascript (Regex): How do i replace (Backslash + Double Quote) pairs?

In Javascript, i want the below original string:
I want to replace \"this\" and \"that\" words, but NOT the one "here"
.. to become like:
I want to replace ^this^ and ^that^ words, but NOT the one "here"
I tried something like:
var str = 'I want to replace \"this\" and \"that\" words, but NOT the one "here"';
str = str.replace(/\"/g,"^");
console.log( str );
Demo: JSFiddle here.
But still .. the output is:
I want to replace ^this^ and ^that^ words, but NOT the one ^here^
Which means i wanted to replace only the \" occurrences but NOT the " alone. But i cannot.
Please help.

As #adeneo's comment, your string was created wrong and not exactly like your expectation. Please try this:
var str = 'I want to replace \\"this\\" and \\"that\\" words, but not the one "here"';
str = str.replace(/\\\"/g,"^");
console.log(str);

You can use RegExp /(")/, String.prototype.lastIndexOf(), String.prototype.slice() to check if matched character is last or second to last match in input string. If true, return original match, else replace match with "^" character.
var str = `I want to replace \"this\" and \"that\" words, but NOT the one "here"`;
var res = str.replace(/(")/g, function(match, _, index) {
return index === str.lastIndexOf(match)
|| index === str.slice(0, str.lastIndexOf(match) -1)
.lastIndexOf(match)
? match
: "^"
});
console.log(res);

The problem with String.prototype.replace is that it only replaces the first occurrence without Regular Expression. To fix this, you need to add a g and the end of the RegEx, like so:
var mod = str => str.replace(/\\\"/g,'^');
mod('I want to replace \\"this\\" and \\"that\\" words, but NOT the one "here"');
A less effective but easier to understand to do what you wanted is to split the string with the delimiter and then join it with the replacement, like so:
var mod = str => str.split('\\"').join('^');
mod('I want to replace \\"this\\" and \\"that\\" words, but NOT the one "here"');
Note: You can wrap a string with either ' or ". Suppose your string contains ", i.e. a"a, you will need to put an \ in front of the " as "a"a" causes syntax error. 'a"a' won't cause syntax error as the parser knows the " is part of the string, but when you put a \ in front of " or any other special characters, it means the following character is a special character. So 'a\"a' === 'a"a' === "a\"a". If you want to store \, you will need to use \ regardless of the type of quote you use, so to store \", you will need to use '\\"', '\\\"' or "\\\"".

javascript - replace dash (hyphen) with a space

I have been looking for this for a while, and while I have found many responses for changing a space into a dash (hyphen), I haven't found any that go the other direction.
Initially I have:
var str = "This-is-a-news-item-";
I try to replace it with:
str.replace("-", ' ');
And simply display the result:
alert(str);
Right now, it doesn't do anything, so I'm not sure where to turn. I tried reversing some of the existing ones that replace the space with the dash, and that doesn't work either.
Thanks for the help.

This fixes it:
let str = "This-is-a-news-item-";
str = str.replace(/-/g, ' ');
alert(str);
There were two problems with your code:
First, String.replace() doesn’t change the string itself, it returns a changed string.
Second, if you pass a string to the replace function, it will only replace the first instance it encounters. That’s why I passed a regular expression with the g flag, for 'global', so that all instances will be replaced.

replace() returns an new string, and the original string is not modified. You need to do
str = str.replace(/-/g, ' ');

I think the problem you are facing is almost this: -
str = str.replace("-", ' ');
You need to re-assign the result of the replacement to str, to see the reflected change.
From MSDN Javascript reference: -
The result of the replace method is a copy of stringObj after the
specified replacements have been made.
To replace all the -, you would need to use /g modifier with a regex parameter: -
str = str.replace(/-/g, ' ');

var str = "This-is-a-news-item-";
while (str.contains("-")) {
str = str.replace("-", ' ');
}
alert(str);
I found that one use of str.replace() would only replace the first hyphen, so I looped thru while the input string still contained any hyphens, and replaced them all.
http://jsfiddle.net/LGCYF/

In addition to the answers already given you probably want to replace all the occurrences. To do this you will need a regular expression as follows :
str = str.replace(/-/g, ' '); // Replace all '-' with ' '

Use replaceAll() in combo with trim() may meet your needs.
const str = '-This-is-a-news-item-';
console.log(str.replaceAll('-', ' ').trim());

Imagine you end up with double dashes, and want to replace them with a single character and not doubles of the replace character. You can just use array split and array filter and array join.
var str = "This-is---a--news-----item----";
Then to replace all dashes with single spaces, you could do this:
var newStr = str.split('-').filter(function(item) {
item = item ? item.replace(/-/g, ''): item
return item;
}).join(' ');
Now if the string contains double dashes, like '----' then array split will produce an element with 3 dashes in it (because it split on the first dash). So by using this line:
item = item ? item.replace(/-/g, ''): item
The filter method removes those extra dashes so the element will be ignored on the filter iteration. The above line also accounts for if item is already an empty element so it doesn't crash on item.replace.
Then when your string join runs on the filtered elements, you end up with this output:
"This is a news item"
Now if you were using something like knockout.js where you can have computer observables. You could create a computed observable to always calculate "newStr" when "str" changes so you'd always have a version of the string with no dashes even if you change the value of the original input string. Basically they are bound together. I'm sure other JS frameworks can do similar things.

if its array like
arr = ["This-is-one","This-is-two","This-is-three"];
arr.forEach((sing,index) => {
arr[index] = sing.split("-").join(" ")
});
Output will be
['This is one', 'This is two', 'This is three']

How to read all string inside parentheses using regex

I wanted to get all strings inside a parentheses pair. for example, after applying regex on
"fun('xyz'); fun('abcd'); fun('abcd.ef') { temp('no'); "
output should be
['xyz','abcd', 'abcd.ef'].
I tried many option but was not able to get desired result.
one option is
/fun\((.*?)\)/gi.exec("fun('xyz'); fun('abcd'); fun('abcd.ef')").

Store the regex in a variable, and run it in a loop...
var re = /fun\((.*?)\)/gi,
string = "fun('xyz'); fun('abcd'); fun('abcd.ef')",
matches = [],
match;
while(match = re.exec(string))
matches.push(match[1]);
Note that this only works for global regex. If you omit the g, you'll have an infinite loop.
Also note that it'll give an undesired result if there a ) between the quotation marks.

You can use this code will almost do the job:
"fun('xyz'); fun('abcd'); fun('abcd.ef')".match(/'.*?'/gi);
You'll get ["'xyz'", "'abcd'", "'abcd.ef'"] which contains extra ' around the string.

The easiest way to find what you need is to use this RegExp: /[\w.]+(?=')/g
var string = "fun('xyz'); fun('abcd'); fun('abcd.ef')";
string.match(/[\w.]+(?=')/g); // ['xyz','abcd', 'abcd.ef']
It will work with alphanumeric characters and point, you will need to change [\w.]+ to add more symbols.