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Whats wrong with this regex logic

I am trying to fetch the value after equal sign, its works but i am getting duplicated values , any idea whats wrong here?
// Regex for finding a word after "=" sign
var myregexpNew = /=(\S*)/g;
// Regex for finding a word before "=" sign
var mytype = /(\S*)=/g;
//Setting data from Grid Column
var strNew = "QCById=20";
var matchNew = myregexpNew.exec(strNew);
var newtype = mytype.exec(strNew);
alert(matchNew);
https://jsfiddle.net/6vjjv0hv/

exec returns an array, the first element is the global match, the following ones are the submatches, that's why you get ["=20", "20"] (using console.log here instead of alert would make it clearer what you get).
When looking for submatches and using exec, you're usually interested in the elements starting at index 1.
Regarding the whole parsing, it's obvious there are better solution, like using only one regex with two submatches, but it depends on the real goal.

You can try without using Regex like this:
var val = 'QCById=20';
var myString = val.substr(val.indexOf("=") + 1);
alert(myString);
Presently exec is returning you the matched value.

REGEXP.exec(SOMETHING) returns an array (see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/exec).
The first item in the array is the full match and the rest matches the parenthesized substrings.

You do not get duplicated values, you just get an array of a matched value and the captured text #1.
See RegExp#exec() help:
If the match succeeds, the exec() method returns an array and updates properties of the regular expression object. The returned array has the matched text as the first item, and then one item for each capturing parenthesis that matched containing the text that was captured.
Just use the [1] index to get the captured text only.
var myregexpNew = /=(\S*)/g;
var strNew = "QCById=20";
var matchNew = myregexpNew.exec(strNew);
if (matchNew) {
console.log(matchNew[1]);
}
To get values on both sides of =, you can use /(\S*)=(\S*)/g regex:
var myregexpNew = /(\S*)=(\S*)/g;
var strNew = "QCById=20";
var matchNew = myregexpNew.exec(strNew);
if (matchNew) {
console.log(matchNew[1]);
console.log(matchNew[2]);
}
Also, you may want to add a check to see if the captured values are not undefined/empty since \S* may capture an empty string. OR use /(\S+)=(\S+)/g regex that requires at least one non-whitespace character to appear before and after the = sign.

Capitalize the first letter of each word

var name = "AlbERt EINstEiN";
function nameChanger(oldName) {
var finalName = oldName;
// Your code goes here!
finalName = oldName.toLowerCase();
finalName = finalName.replace(finalName.charAt(0), finalName.charAt(0).toUpperCase());
for(i = 0; i < finalName.length; i++) {
if (finalName.charAt(i) === " ")
finalName.replace(finalName.charAt(i+1), finalName.charAt(i+1).toUpperCase());
}
// Don't delete this line!
return finalName;
};
// Did your code work? The line below will tell you!
console.log(nameChanger(name));
My code as is, returns 'Albert einstein'. I'm wondering where I've gone wrong?
If I add in
console.log(finalName.charAt(i+1));
AFTER the if statement, and comment out the rest, it prints 'e', so it recognizes charAt(i+1) like it should... I just cannot get it to capitalize that first letter of the 2nd word.

There are two problems with your code sample. I'll go through them one-by-one.
Strings are immutable
This doesn't work the way you think it does:
finalName.replace(finalName.charAt(i+1), finalName.charAt(i+1).toUpperCase());
You need to change it to:
finalName = finalName.replace(finalName.charAt(i+1), finalName.charAt(i+1).toUpperCase());
In JavaScript, strings are immutable. This means that once a string is created, it can't be changed. That might sound strange since in your code, it seems like you are changing the string finalName throughout the loop with methods like replace().
But in reality, you aren't actually changing it! The replace() function takes an input string, does the replacement, and produces a new output string, since it isn't actually allowed to change the input string (immutability). So, tl;dr, if you don't capture the output of replace() by assigning it to a variable, the replaced string is lost.
Incidentally, it's okay to assign it back to the original variable name, which is why you can do finalName = finalName.replace(...).
Replace is greedy
The other problem you'll run into is when you use replace(), you'll be replacing all of the matching characters in the string, not just the ones at the position you are examining. This is because replace() is greedy - if you tell it to replace 'e' with 'E', it'll replace all of them!
What you need to do, essentially, is:
Find a space character (you've already done this)
Grab all of the string up to and including the space; this "side" of the string is good.
Convert the very next letter to uppercase, but only that letter.
Grab the rest of the string, past the letter you converted.
Put all three pieces together (beginning of string, capitalized letter, end of string).
The slice() method will do what you want:
if (finalName.charAt(i) === " ") {
// Get ONLY the letter after the space
var startLetter = finalName.slice(i+1, i+2);
// Concatenate the string up to the letter + the letter uppercased + the rest of the string
finalName = finalName.slice(0, i+1) + startLetter.toUpperCase() + finalName.slice(i+2);
}
Another option is regular expression (regex), which the other answers mentioned. This is probably a better option, since it's a lot cleaner. But, if you're learning programming for the first time, it's easier to understand this manual string work by writing the raw loops. Later you can mess with the efficient way to do it.
Working jsfiddle: http://jsfiddle.net/9dLw1Lfx/
Further reading:
Are JavaScript strings immutable? Do I need a "string builder" in JavaScript?
slice() method

You can simplify this down a lot if you pass a RegExp /pattern/flags and a function into str.replace instead of using substrings
function nameChanger(oldName) {
var lowerCase = oldName.toLowerCase(),
titleCase = lowerCase.replace(/\b./g, function ($0) {return $0.toUpperCase()});
return titleCase;
};
In this example I've applied the change to any character . after a word boundary \b, but you may want the more specific /(^| )./g

Another good answer to this question is to use RegEx to do this for you.
var re = /(\b[a-z](?!\s))/g;
var s = "fort collins, croton-on-hudson, harper's ferry, coeur d'alene, o'fallon";
s = s.replace(re, function(x){return x.toUpperCase();});
console.log(s); // "Fort Collins, Croton-On-Hudson, Harper's Ferry, Coeur D'Alene, O'Fallon"
The regular expression being used may need to be changed up slightly, but this should give you an idea of what you can do with regular expressions
Capitalize Letters with JavaScript

The problem is twofold:
1) You need to return a value for finalName.replace, as the method returns an element but doesn't alter the one on which it's predicated.
2) You're not iterating through the string values, so you're only changing the first word. Don't you want to change every word so it's in lower case capitalized?
This code would serve you better:
var name = "AlbERt EINstEiN";
function nameChanger(oldName) {
// Your code goes here!
var finalName = [];
oldName.toLowerCase().split(" ").forEach(function(word) {
newWord = word.replace(word.charAt(0), word.charAt(0).toUpperCase());
finalName.push(newWord);
});
// Don't delete this line!
return finalName.join(" ");
};
// Did your code work? The line below will tell you!
console.log(nameChanger(name));

if (finalName.charAt(i) === " ")
Shouldn't it be
if (finalName.charAt(i) == " ")
Doesn't === check if the object types are equal which should not be since one it a char and the other a string.

How to read only part of a string in Javascript

I am pulling in a string from another web page. I want to read that string into a variable but only after a certain point. Eg:
#stringexample
var variable;
I want variable to equal stringexample but not contain the # how could I do this?
This is how I am using the variable at the moment.
$("#Outputajax").load("folder/"+ variable +".html");
This is the way that works but isn't a variable.
$("#Outputajax").load("folder/webpage.html");

If you just want to trim of the first character, then you can use substring...
var input = "#stringexample";
input = input.substring(1);
//input = "stringexample"
Here is a working example

var myVariable = stringExample.replace('#','');

Could just use variable.substr(1) to cut off the first character.
If you want to specifically remove the hash from the start (but do nothing if the hash isn't there), try variable.replace(/^#/,"")

I understand you want to get everything in the string AFTER the hashtag. The other solutions will leave anything ahead of the hashtag in as well. And substring does not work if the hashtag is not the first symbol.
variable= "#stringexample".split("#")[1];
This splits the string into an array of strings, with the parameter as the point where to split, without including the parameter itself. There will be an empty string as the first parameter, and everything after the hashtag is the second string.

var slicer = function(somestring){
var parsedString = somestring;
parsedString = parsedString.slice(1);
return parsedString
}
// run from yors function with some string
var someYouVar = slicer("#something")

remove values from a string

Does anyone know how I would remove all leading zeros from a string.
var str = 000890
The string value changes all the time so I need it to be able to remove all 0s before a number greater than 0. So in the example above it needs to remove the first three 0s. So the result would be 890

It looks like we each have our own ways of doing this. I've created a test on jsperf.com, but the results are showing
String(Number('000890'));
is the quickest (on google chrome).
Here are the numbers for the updated test based on #BenLee's comment for Firefox, IE, and Chrome.

See: this question
var resultString = str.replace(/^[0]+/g,"");

var resultString = str.replace(/^[0]+/g,"");

I think a function like this should work
function replacezeros(text){
var newText = text.replace(/^[0]+/g,"");
return newText;
}

If it needs to stay as a string, cast it to a number, and cast it back to a string:
var num = '000123';
num = String(Number(num));
console.log(num);
You could also use the shorthand num = ''+(+num);. Although, I find the first form to be more readable.

parseInt('00890', 10); // returns 890
// or
Number('00890'); // returns 890

If your problem really is as you defined it, then go with one of the regex-based answers others have posted.
If the problem is just that you have a zero-padded integer in your string and need to manipulate the integer value without the zero-padding, you can just convert it to an integer like this:
parseInt("000890", 10) # => 890
Note that the result here is the integer 890 not the string "890". Also note that the radix 10 is required here because the string starts with a zero.

return str.replace(/^0+(.)/, '$1'));
That is: replace maximum number of leading zeros followed by any single character (which won't be a zero), with that single character. This is necessary so as not to swallow up a single "0"

you can simply do that removing the quotation marks.
var str = 000890;
//890
var str = "000890";
//000890

Remove part an ever-changing text string with javascript?

I have a string of text "AB-123-2011-07-09", and need to remove everything except "123", then add a "#" sign to the end result.
The string "123" is ever increasing in number, as is the "2011-07-09" (a date). Only "AB" stays the same.
So the end result would be: #123
Is this possible?
Thanks.
EDIT: Just to clarify, I was needing a script that could globally search a page and replace any text which had the format of "AB-xxx-xxxx-xx-xx" with just the digits highlighted here in bold, then adding the "#" before it.
Currently there are only 3 digits in that position, but in the future there may be four.
My code:
function Replace() {
var OldString = "AB-123-2011-07-09";
var NewString = OldString.replace(/^AB-(\d+)-.*/, "#$1");
document.body.innerHTML = document.body.innerHTML.replace(OldString, NewString);
}
window.onload = Replace();
So far it only replaces 1 instance of the string, and uses a fixed string ("AB-123-2011-07-09").
What regular expression do I need to make the 'OldString' dynamic, rather than it being fixed as it is now?

var data = "AB-123-2011-07-09";
var field = data.split('-')[1];
document.write("#" + field);
http://jsfiddle.net/efortis/8acDr/

The following regex would work, but in this case I don't think you need a regex at all (as #Eric has already shown).
"AB-123-2011-07-09".replace(/^AB-(\d+)-.*/, "#$1");
This results in the value #123
http://jsfiddle.net/3XhbE/

Does this work?
var result = mystring.replace(new RegExp(AB-([0-9]+)-[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9], "g"),"#$1");
mystring is the "AB-123-2011-07-09" string and result would be "#123".

This is of course possible. This regex would do the trick:
“AB-123-2011-07-09“.replace(/^AB-(\d+)-\d+-\d+-\d+$/, “#$1“);
It also checks you given syntax and that there is nothing else in the string.
migg