how to check if email is valid javascript code example

Example 1: javascript regex email

function validateEmail (emailAdress)
{
  let regexEmail = /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/;
  if (emailAdress.match(regexEmail)) {
    return true; 
  } else {
    return false; 
  }
}

let emailAdress = "[email protected]";
console.log(validateEmail(emailAdress));

Example 2: email regex javscript

function validateEmail(email) {
    var re = /^(([^<>()\[\]\\.,;:\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,}))$/;
    return re.test(String(email).toLowerCase());
}

Example 3: js validate email

function validateEmail(email) {
  var re = /^(([^<>()[\]\\.,;:\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,}))$/;
  return re.test(email);
}

Example 4: email validation js

/// if you want  create your regular expression then you can  follow this site 
/////https://regex101.com///////
<!DOCTYPE html>
<html>
<head>
	<title></title>
</head>
<body>
<form method="post" action="">
	Email:<input type="text"  id="email" onkeyup="validation()">
	</form>
</body>
<script type="text/javascript">
	function validation(){
	var email=document.getElementById("email").value;///get id with value 
	var emailpattern=/^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/;////Regular expression
	if(emailpattern.test(email))
	{
		document.getElementById("email").style.backgroundColor='yellow';
    }
    else
    {
    	document.getElementById("email").style.backgroundColor='red'; }
	}

</script>
</html>