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JS Regex url validation

I tried to validate url with or without http No matter what i did the function return false.
I checked my regex string in this site:
http://regexr.com/
And its seen as i expect.
function isUrlValid(userInput) {
var regexQuery = "/(http(s)?://.)?(www\.)?[-a-zA-Z0-9#:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9#:%_\+.~#?&//=]*)/";
var url = new RegExp(regexQuery,"g");
if (url.test(userInput)) {
alert('Great, you entered an E-Mail-address');
return true;
}
return false;
}
I fix the problem by change the .test to .match and leave the regex as is.

I change the function to Match + make a change here with the slashes and its work: (http(s)?://.)
The fixed function:
function isUrlValid(userInput) {
var res = userInput.match(/(http(s)?:\/\/.)?(www\.)?[-a-zA-Z0-9#:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9#:%_\+.~#?&//=]*)/g);
if(res == null)
return false;
else
return true;
}

I believe the other answer will reject some valid url's (like domain names in uppercase or long sub-domains) and allow some invalid ones (like http://www.-example-.com or www.%#&.com). I tried to take into account a number of additional url syntax rules (without getting into internationalisation).
function isUrlValid(userInput) {
var regexQuery = "^(https?://)?(www\\.)?([-a-z0-9]{1,63}\\.)*?[a-z0-9][-a-z0-9]{0,61}[a-z0-9]\\.[a-z]{2,6}(/[-\\w#\\+\\.~#\\?&/=%]*)?$";
var url = new RegExp(regexQuery,"i");
return url.test(userInput);
}
var input = ["https://o.sub-domain.example.com/foo/bar?foo=bar&boo=far#a%20b",
"HTTP://EX-AMPLE.COM",
"example.c",
"example-.com"];
for (var i in input) document.write(isUrlValid(input[i]) + ": " + input[i] + "<br>");
To also allow IP addresses and port numbers, the regex is:
"^(https?://)?(((www\\.)?([-a-z0-9]{1,63}\\.)*?[a-z0-9][-a-z‌​0-9]{0,61}[a-z0-9]\\‌​.[a-z]{2,6})|((\\d{1‌​,3}\\.){3}\\d{1,3}))‌​(:\\d{2,4})?(/[-\\w#‌​\\+\\.~#\\?&/=%]*)?$‌​"
To also allow query strings without a slash between the domain name and the question mark (which is theoretically not allowed, but works in most real-life situations), the regex is:
"^(https?://)?(((www\\.)?([-a-z0-9]{1,63}\\.)*?[a-z0-9][-a-z‌​0-9]{0,61}[a-z0-9]\\‌​.[a‌​-z]{2,6})|((\\d‌​{1,3}\\.){3}\\d{1,3}‌​))(:\\d{2,4})?((/|\\‌​?)[-\\w#\\+\\.~#\\?&‌​/=%]*)?$"
To also make sure that every % is followed by a hex number, the regex is:
"^(https?://)?(((www\\.)?([-a-z0-9]{1,63}\\.)*?[a-z0-9][-a-z‌​0-9]{0,61}[a-z0-9]\\‌​.[a-z]{2,6})|((\\d{1‌​,3}\\.){3}\\d{1,3}))‌​(:\\d{2,4})?((/|\\?)‌​(((%[0-9a-f]{2})|[-\‌​\w#\\+\\.~#\\?&/=])*‌​))?$"
(Note: as John Wu mentioned in a comment, there are valid single-letter domains).

Actually, this question needs a powerful regex and the following code is not very hard to understand, please see below(ES6 - TypeScript):
const isValidUrl = (url: string): boolean => {
const urlRegex = /^((http(s?)?):\/\/)?([wW]{3}\.)?[a-zA-Z0-9\-.]+\.[a-zA-Z]{2,}(\.[a-zA-Z]{2,})?$/g;
const result = url.match(urlRegex);
return result !== null;
};

Try this code.
function CheckURL(fieldId, alertMessage) {
var url = fieldId.value;
if(url !== "")
{
if (url.match(/(http(s)?:\/\/.)?(www\.)?[-a-zA-Z0-9#:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9#:%_\+.~#?&//=]*)/g) !== null)
return true;
else {
alert(alertMessage);
fieldId.focus();
return false;
}
}
}
var website = document.getElementById('Website');
if (!CheckURL(website, "Enter a valid website address")) {
return false;
}

Regular expression validation - initialization error in Javascript

I am trying to write a function in Javascript to validate email address. Here is the function.
function validateEmailAddress() {
var patternForEmail = /^([a-zA-Z0-9_\-\.]+)#((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})$/;
var regexPatternForEmail = new RegExp(patternForEmail, 'i');
// Email address and the Confirm Email address values should match
if ($('#txtEmail').val() != $('#txtConfirmEmail').val()) {
$('#dvErrorMsg').html("Email addresses do not match.");
$('#txtEmail').focus();
return false;
}
else if (!regexPatternForEmail.test($('#txtEmail').val())) {
$('#dvErrorMsg').html("Please enter a valid email address.");
$('#txtEmail').focus();
return false;
}
else
return true;
}
The problem here is I am getting an error, 'Syntax error in regular expression' during RegExp object instantiation.
I tried debuggin in IE 11 and that's where i found the error.
Could someone please suggest me a solution for this.
Screen shot taken while debugging:

You don't need to create another regex variable using RegExp constructor. Just use only the below.
var patternForEmail = /^([a-zA-Z0-9_\-\.]+)#((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})$/i;
i at the last called case-insensitive modifier which helps to do a case-insensitive match.
Example:
> var patternForEmail = /^([a-zA-Z0-9_\-\.]+)#((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})$/i;
> patternForEmail.test('foo#bar.com')
true
> patternForEmail.test('#foo#bar.com')
false

In most of the times this kinds of errors occurs because of browser compatibility , so always we need to use the codes which can be run in all the browsers. I hope the following changes will help you.
var patternForEmail = /^([\w-]+(?:\.[\w-]+)*)#((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i;
then you can match the expression using
if (patternForEmail.test($('#txtEmail').val())) {
$('#dvErrorMsg').html("Please enter a valid email address.");
$('#txtEmail').focus();
return false;
}
or else you can use match() function also which will be more flexible for all the browsers.
var email = $('#txtEmail').val();
if (!email.match(/^([\w-]+(?:\.[\w-]+)*)#((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i)) {
$('#dvErrorMsg').html("Please enter a valid email address.");
$('#txtEmail').focus();
return false;
}

jQuery Validation plugin custom method using regex

I need to make a new method for jQuery Validator and don't know where to start.
I would like it check that the email entered includes: '#specificdomain.com'.
But that it is also the very last part of the input. For example #specificdomain.comChris would not do.
<script type="text/javascript">
jQuery.validator.addMethod("mustinclude", function(value, element) {
return this.optional(element) || value == ?
}, "must include #specificdomain.com at the end of the text input");
$(document).ready(function(){ .....
So far I've only come across value == value.match(), hence this is where I've got stuck.
Cheers Chris
jQuery.validator.addMethod('matchDomain', function(value, element) {
var s=value;
var split = s.split('#');
var regex = /^([a-zA-Z0-9_.+-])+$/;
var s2="#allcoles.com";
var optionalValue = this.optional(element);
if (optionalValue) {
return optionalValue;
}
if(regex.test(split[0]) && s2.equals(split[1]))
{
return true;
}
else
{
return false;
}
}, 'Please specify a #allcoles.com email');

The following worked for me:
jQuery.validator.addMethod('matchDomain', function(value, element) {
var s=value;
var split = s.split('#');
var regex = /^([a-zA-Z0-9_.+-])+$/;
**var s2="allcoles.com";** //The split array is the domain excluding the #
**var optionalValue = this.optional(element);** //This is how other methods in alternativeMethods.js Validator handle this.
**//Debugging - This is useful to see visually what is happening
//alert(split[0]); // Shows the inputted username i.e chris or smokey
//alert(split[1]); // Shows the inputted domain
//alert(regex.test(split[0])); //Shows unfilled inputs problem or bad characters, true if good, false if bad
//alert(s2 == split[1]);** // Shows if the inputted domain matches variable s2, if it does we get a true
if (optionalValue) {
return optionalValue;
}
**if(regex.test(split[0]) && (s2 == split[1]))** // has to be == not equals
{
return true;
}
else
{
return false;
}
}, 'Please specify a #allcoles.com email');

var s="abc#specificdomain.com"; OR var s=value;
var split = s.split('#');
var regex = /^([a-zA-Z0-9_.+-])/;
var s2="#specificdomain.com";
if(regex.test(split[0]) && s2 == split[1])
return true;
else
return false;

Validate email as you type

I want to validate input as I type so I use onkeyup event to do so, but if I validate an email regex "name#domain.com", as soon as user starts to type it throws an error - first character doesnt match regex...
So I wrote this:
var addValidation = function (patterns) {
var index = patterns.length; //I know I can avoid this
while (index--) {
patterns[index] = new RegExp(patterns[index]);
}
index = 0;
var current = patterns[index],
matchExact = function (patt, str) {
var match = str.match(patt);
return match !== null && str === match[0];
};
return function () {
var str = this.value;
if (!matchExact(current, str) ) {
var tmp = patterns[index + 1] ?
new RegExp(current.source + patterns[index + 1].source) :
false;
if (tmp && matchExact(tmp, str)) {
current = tmp;
index++;
}
else {
alert("Wrong");
}
}
}
};
document.getElementById("x").onkeyup = addValidation(["[a-zA-Z0-9\\.]+", "#{1}", "[a-zA-Z0-9]+", "\\.{1}", "[a-zA-Z]{1,3}"]);
It seems to work, but... it's ugly and it will alert you if you do step back (eg. "name#" and you press backspace).
I know that Dojo's validation is great, but I do not want to use Dojo. Are there any better ways to achieve that?
//EDIT: http://livedocs.dojotoolkit.org/dijit/form/ValidationTextBox this is an example, but you can define your own pattern (like email regex) and it will validate it perfectly.

Add interval before validation will start:
var t;
document.getElementById("x").onkeyup = function () {
if (t) {
clearTimeout(t);
}
t = setTimeout(function () {
//do validation
}, 1000)
}

Don't ever try to validate an email address with a regualr expression. You'll either end up allowing addresses which are not valid, or block email addresses which are perfectly valid and just annoy your visitors. It's also worth bearing in mind that the best regex so far for validating email addresses is this:
http://www.ex-parrot.com/pdw/Mail-RFC822-Address.html

RegEx validation of html form in external .js

I am trying to validate a html form using a javascript function, but the function is never matching the values to regex even when they are correct. This is what I have:
function validateForms(form){
var usZipRegex = '^\d{5}[[$-.+ ]?\d{4}]?$|^\d{5}$';
var canZipRegex = '^[ABCEGHJKLMNPRSTVWXY][\d][ABCEGHJKLMNPRSTVWXYZ][\W]?[\d][ABCEGHJKLMNPRSTVWXYZ][\d]$';
var nameRegex = '^[A-Za-z][ -a-zA-Z]+$';
var emailRegex = '^[^\.#]([\w]*\.)*[^\.#]*#[a-zA-Z0-9-]{1,63}(\.[a-zA-Z0-9-]{1,63})+$';
var name = form.name.value;
var zip = form.zip.value;
var email = form.email.value;
var comment = form.comment.value
if(name == "") {
alert('You must enter your name.');
return false;
}
if(name != nameRegex) {
alert('You have entered an invalid name.');
return false;
}
if(email == "") {
alert('You must enter your email.');
return false;
}
if(email != emailRegex) {
alert('You have entered an invalid email.');
return false;
}
if(zip == "") {
alert('You must enter your zip code.');
return false;
}
if((zip != usZipRegex) & (zip != canZipRegex)) {
alert('You have entered an invalid zip code.');
return false;
}
if(comment == "") {
alert('You must enter a message.');
return false;
}
return true;
}
The (name != nameRegex) parts always return true, but should not. The (name == "") parts do work on their own though.

You're comparing the raw strings, not running the regex. name != nameRegex will always return true unless the person's name is literally ^[A-Za-z][ -a-zA-Z]+$. You need to set up nameRegex properly as a regex object, but in your code, it's just a string. You also need to use test or another one of the RegExp object's methods to check for a match, not the ==/!= operators. This is true for the other patterns as well.
Constructing a regex is done one of two ways:
var regex1 = /[a-z0-9]/;
var regex2 = new RegExp('[a-z0-9]');
If you do it like this, though, it's just a string:
var notARegex = '[a-z0-9]';
Your code should be closer to this style:
var nameRegex = /^[A-Za-z][-a-zA-Z ]+$/; //note that the hyphen has been moved
//...
if (!nameRegex.test(name)) {
alert('You have entered an invalid name.');
return false;
}
Edit: There's more going wrong here. Your other regex code could use some major improvements:
var usZipRegex = /^\d{5}([$.+ -]?\d{4})?$/;
var canZipRegex = /^(?![DFIOQU])[A-Y]\d(?![DFIOQU])[A-Z]\W?\d(?![DFIOQU])[A-Z]\d$/;
var nameRegex = /^[a-z][a-z\s-]+$/i;
var emailRegex = /^[^.#]+#[^.#]{1,63}(\.[^.#]{1,63})+$/i';
I don't know if your Canadian zip code pattern is correct, but the email one was definitely wrong (email is WAY more complicated than you think, so it's best to be very permissive with it).