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JavaScript Regular Expression Email Validation [duplicate]

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How do I validate an email address in regex?

Additionally, the second string needs to contain a dot, which has an additional 2-3 characters after that. With that in mind, to generally validate an email address in JavaScript via Regular Expressions, we translate the rough sketch into a RegExp : let regex = new RegExp('[a-z0-9]+@[a-z]+\.

How do you check if a string is an email JavaScript?

const validateEmail = (email) => { return String(email) . toLowerCase() . match( /^(([^<>()[\]\\.,;:\s@"]+(\. [^<>()[\]\\.,;:\s@"]+)*)|(".

How do I validate an email address in react?

To validate an email in an input field in React, use the test() method on the following regular expression - /\S+@\S+\. \S+/ . The test method will return true if the email is valid and false otherwise.


If you define your regular expression as a string then all backslashes need to be escaped, so instead of '\w' you should have '\\w'.

Alternatively, define it as a regular expression:

var pattern = /^\w+@[a-zA-Z_]+?\.[a-zA-Z]{2,3}$/; 

BTW, please don't validate email addresses on the client-side. Your regular expression is way too simple to pass for a solid implementation anyway.

See the real thing here: http://www.ex-parrot.com/~pdw/Mail-RFC822-Address.html


this is the one i am using on my page.

http://www.zparacha.com/validate-email-address-using-javascript-regular-expression/

/^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,6}$/


I've been using this function for a while. it returns a boolean value.

// Validates email address of course.
function validEmail(e) {
    var filter = /^\s*[\w\-\+_]+(\.[\w\-\+_]+)*\@[\w\-\+_]+\.[\w\-\+_]+(\.[\w\-\+_]+)*\s*$/;
    return String(e).search (filter) != -1;
}

You may be interested in this question (or this one), which highlights the fact that identifying valid email addresses via regexps is a very hard problem to solve (if at all solvable)


with more simple regex

Here it is :

var regexEmail = /\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*/;
var email = document.getElementById("txtEmail");

if (regexEmail.test(email.value)) {
    alert("It's Okay")
} else {
    alert("Not Okay")

}

good luck.


Sometimes most of the registration and login page need to validate email. In this example you will learn simple email validation. First take a text input in html and a button input like this

<input type='text' id='txtEmail'/>
<input type='submit' name='submit' onclick='checkEmail();'/>

<script>
    function checkEmail() {
        var email = document.getElementById('txtEmail');
        var filter = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
        if (!filter.test(email.value)) {
            alert('Please provide a valid email address');
            email.focus;
            return false;
        }
    }
</script>

you can also check using this regular expression

<input type='text' id='txtEmail'/>
<input type='submit' name='submit' onclick='checkEmail();'/>

<script>
    function checkEmail() {

        var email = document.getElementById('txtEmail');
        var filter = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;

        if (!filter.test(email.value)) {
            alert('Please provide a valid email address');
            email.focus;
            return false;
        }
    }
</script>

Check this demo output which you can check here

function checkEmail() {
        var email = document.getElementById('txtEmail');
        var filter = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
        if (!filter.test(email.value)) {
            alert('Please provide a valid email address');
            email.focus;
            return false;
        }
    }
<input type='text' id='txtEmail'/>
<input type='submit' name='submit' onclick='checkEmail();'/>

if email invalid then give alert message , if valid email then no alert message . for more info about regular expression

https://www.w3schools.com/jsref/jsref_obj_regexp.asp

hope it will help you