How to validate Email address in php in javascript?

In this tutorial learn how to validate email address in javascript, Validate Email address  in javascript, email validation using Example of valid email id

HTML Form - email validation

In HTML Form - Email validation in javascript here are the steps  its easy to do email validation in javascript

JavaScript code to validate an email id

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

if (!filter.test(mail)) {
    alert('Please provide a valid email address');
    email.focus;
    return false;
  }