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javascript : problem with regular expression

I'm trying to validate the value of an input text field with the following code:
function onBlurTexto(value) {
var regexNIT = "([a-zA-z]|[0-9]|[&#,#.ÑñáéíóúÁÉÍÓÚ\|\s])";
regexCompilado = new RegExp(regexNIT);
if (!(regexCompilado.test(value))) {
alert("Wrong character in text :(");
return false;
} else {
return true;
}
}
But when i enter this text:
!65a
the function returns true (as you can see, the "!" character does not exist in the regular expression)
I'm not an expert in regular expressions, so i think i am missing something in the building of this reg.exp.
How can i put this regular expression to work?
Thanks in advance.
EDIT
i am so sorry ... i should remove the references to the variable "regexpValidar" before posting the issue. I modified the sample. Thanks #TecBrat

You should provide the start (^) and end ($) flags to your regex. Now you are matching 65a since you have alternate sets.
This should work /^([a-zA-z]|[0-9]|[&#,#.ÑñáéíóúÁÉÍÓÚ\|\s])+$/g
Demo: https://regex101.com/r/zo2MpN/3

RegExp.test looks for a match in the string, it doesn't verify that the whole string matches the regex. In order to do the latter, you need to add start and end anchors to your regex (i.e. '^' at the start and '$' at the end, so you have "^your regex here$").
I also just noticed that your regex is currently matching only one character. You probably want to add a '+' after the parens so that it matches one or more:
"^([a-zA-z]|[0-9]|[&#,#.ÑñáéíóúÁÉÍÓÚ\|\s])+$"

This is wrong. the variable you use doesn't has anything. Try this instead.
var regexCompilado = new RegExp(regexNIT);

validate string which has only one special character using javascript

I know there are several question like this on Stack-overflow, but I can't seem to get a straight answer out of the questions already posted.Looking forward if someone can help me.
I want to validate a string & return TRUE if it satisfies below condition
String contains only one special character i.e _ (underscore)
& this special character should not appear at beginning or end of the string
Example:
var demo1="23dsfXXXa32_XXXX" // Valid, should returns TRUE
var demo2="_23dsfXXXa32_XXXX" // Invalid,should returns FALSE
var demo3= "23dsfXXXa32XXXX_" //invalid,should returns FALSE
var demo4= "_" //invalid,should returns FALSE
var demo5= "&sdfsa_XX";// returns false
Tried: FIDDLE
if(/^[a-zA-Z0-9_ ]*$/.test(demo1) == true) {
alert('Valid String');
}
Result: Not functioning as per expected

Since you've said you require that the character be there, one way is to do it with a regular expression is with a negated character class at each end with a non-negated one in the middle:
var rex = /^[^_]+[_][^_]+$/;
That only handle underscores; add other "special" characters to all three character classes there.
How that works:
^ matches start of string
[^_]+ requires one or more characters not in the class
[_] requires exactly one character in the class
[^_]+ requires one or more characters not in the class
$ matches end of string

You could simplify it by using indexOf to verify that its not in the first or last position and split to see if its there only once. This is usually faster than a regex pattern.
function checkString(str){
return str.indexOf("_") !== 0 && str.indexOf("_") !== str.length-1 && str.split("_") === 2;
}

Javascript Regex doesn't match with my String

I have the following String :
var resultLine= "[UT] - GSM incoming call : STEP 1 - Simulate reception from server (1)Rerun3713 msAssertion ok"
And the following code which is responsible to check of the String matched with the Regex :
var resultRE = /^([ \w-]*: )?(.+) \((\d+), (\d+), (\d+)\)Rerun/;
var resultMatch = resultLine.match(resultRE);
if (resultMatch) {
return true;
} else {
return false;
}
In this case, i have an error in my Regex because i always get "false".
Where is my mistake ?

I would recommend the following pattern based on what it appears you are looking for:
var resultRE = /^([\[ \w\]-]*: )(.+) \(([0-9, ]*)\)Rerun(.*)$/
This should force all capture groups to exist, even if they are empty, and will allow for multiple numbers before Rerun as you seem to expect.

This matches nothing in your string
([ \w-]*: )?
Since it was optional, that doesn't matter because it gets caught by the all inclusive
(.+)
If you were trying to match the [UT] part with it's separator, it would look something like this
(\[\w+\][\s\-]*)?
As noted in the comments, you only have one number in parentheses but your regex requires three sets of them, separated by commas. This will allow any number of numbers, separated by commas indefinitely (I don't know if there's a limit or not).
\((\d+,\s)*(\d+)\)
If you need something more specific, you'll have to be more specific about what template your matching, not a specific case. But the best I can figure with what you've provided is
^(\[\w\][\s\-]*)?(.+)\((\d+,\w)*(\d+)\)Rerun

var resultRE = /\((\d+)(?:, (\d+))?(?:, (\d+))?\)Rerun/;
if (resultRE.test(resultLine)) {
var num1 = RegExp.$1,
num2 = RegExp.$2,
num3 = RegExp.$3;
}

Matching special characters and letters in regex

I am trying to validate a string, that should contain letters numbers and special characters &-._ only. For that I tried with a regular expression.
var pattern = /[a-zA-Z0-9&_\.-]/
var qry = 'abc&*';
if(qry.match(pattern)) {
alert('valid');
}
else{
alert('invalid');
}
While using the above code, the string abc&* is valid. But my requirement is to show this invalid. ie Whenever a character other than a letter, a number or special characters &-._ comes, the string should evaluate as invalid. How can I do that with a regex?

Add them to the allowed characters, but you'll need to escape some of them, such as -]/\
var pattern = /^[a-zA-Z0-9!##$%^&*()_+\-=\[\]{};':"\\|,.<>\/?]*$/
That way you can remove any individual character you want to disallow.
Also, you want to include the start and end of string placemarkers ^ and $
Update:
As elclanrs understood (and the rest of us didn't, initially), the only special characters needing to be allowed in the pattern are &-._
/^[\w&.\-]+$/
[\w] is the same as [a-zA-Z0-9_]
Though the dash doesn't need escaping when it's at the start or end of the list, I prefer to do it in case other characters are added. Additionally, the + means you need at least one of the listed characters. If zero is ok (ie an empty value), then replace it with a * instead:
/^[\w&.\-]*$/

Well, why not just add them to your existing character class?
var pattern = /[a-zA-Z0-9&._-]/
If you need to check whether a string consists of nothing but those characters you have to anchor the expression as well:
var pattern = /^[a-zA-Z0-9&._-]+$/
The added ^ and $ match the beginning and end of the string respectively.
Testing for letters, numbers or underscore can be done with \w which shortens your expression:
var pattern = /^[\w&.-]+$/
As mentioned in the comment from Nathan, if you're not using the results from .match() (it returns an array with what has been matched), it's better to use RegExp.test() which returns a simple boolean:
if (pattern.test(qry)) {
// qry is non-empty and only contains letters, numbers or special characters.
}
Update 2
In case I have misread the question, the below will check if all three separate conditions are met.
if (/[a-zA-Z]/.test(qry) && /[0-9]/.test(qry) && /[&._-]/.test(qry)) {
// qry contains at least one letter, one number and one special character
}

Try this regex:
/^[\w&.-]+$/
Also you can use test.
if ( pattern.test( qry ) ) {
// valid
}

let pattern = /^(?=.*[0-9])(?=.*[!##$%^&*])(?=.*[a-z])(?=.*[A-Z])[a-zA-Z0-9!##$%^&*]{6,16}$/;
//following will give you the result as true(if the password contains Capital, small letter, number and special character) or false based on the string format
let reee =pattern .test("helLo123#"); //true as it contains all the above

I tried a bunch of these but none of them worked for all of my tests. So I found this:
^(?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[^a-zA-Z0-9])(?!.*\s).{8,15}$
from this source: https://www.w3resource.com/javascript/form/password-validation.php

Try this RegEx: Matching special charecters which we use in paragraphs and alphabets
Javascript : /^[a-zA-Z]+(([\'\,\.\-_ \/)(:][a-zA-Z_ ])?[a-zA-Z_ .]*)*$/.test(str)
.test(str) returns boolean value if matched true and not matched false
c# : ^[a-zA-Z]+(([\'\,\.\-_ \/)(:][a-zA-Z_ ])?[a-zA-Z_ .]*)*$

Here you can match with special char:
function containsSpecialChars(str) {
const specialChars = /[`!##$%^&*()_+\-=\[\]{};':"\\|,.<>\/?~]/;
return specialChars.test(str);
}
console.log(containsSpecialChars('hello!')); // 👉️ true
console.log(containsSpecialChars('abc')); // 👉️ false
console.log(containsSpecialChars('one two')); // 👉️ false

How can I implement a live Javascript Regex for phone numbers?

I have a text box and it says "Phone:" as the standard here for phone number is (XXX)-XXX-XXXX
I'd like to have a javascript that automatically puts my numbers into that format if it's not in that format, so if you typed 9993334444 then it would change it automatically on the fly as I'm typing to (999)-333-4444 I have looked around Google for Javascript Phone Regex to no success, maybe a Regex isn't what I'm looking for?

you want to add an onkeyup event with a regex like
this.value = this.value.replace(/^\(?([0-9][0-9][0-9]){1}\)?-?([0-9][0-9][0-9][0-9]){1}-?([0-9][0-9][0-9]){1}$/, '($1)-$2-$3');
Check out http://jsfiddle.net/R8enX/
/ means start/end a regex string
^ means start of matching string
$ means end of matching string
? means 0 or 1 instances (make braces and dashes optional)
[0-9] means any single digit
(x){1} tags x as an expression that we can reference in the replacement with a $ sign
EDIT: realized I missed a digit on the last group of numbers, the jsfiddle will only work (properly) with 3 digits in the last group

To build somewhat on #Andrews answer you can check for a valid (local)phone number via this method. If the number is shorter or larger than 10 digits, it collapses back into an invalid number
-
<input type="text" onBlur="localNumber(this.value)"/>
<div id="output"></div>
-
<script>
var localNumber = function(str){
repl = str.replace(/^([0-9]{3})([0-9]{3})([0-9]{4})$/, "($1)-$2-$3");
outp = document.getElementById('output');
if( repl.match(/\W/) )
{
outp.innerHTML = repl;
}
else
{
outp.innerHTML = 'Invalid number for this region';
}
}
</script>