check if string is an email nodejs code example

Example 1: js check if email is valid

function ValidateEmail(mail) 
{
 if (/^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/.test(myForm.emailAddr.value))
  {
    return (true)
  }
    alert("You have entered an invalid email address!")
    return (false)
}

Example 2: how to validate email in node js

var emailRegex = /^[-!#$%&'*+\/0-9=?A-Z^_a-z{|}~](\.?[-!#$%&'*+\/0-9=?A-Z^_a-z`{|}~])*@[a-zA-Z0-9](-*\.?[a-zA-Z0-9])*\.[a-zA-Z](-?[a-zA-Z0-9])+$/;

function isEmailValid(email) {
    if (!email)
        return false;

    if(email.length>254)
        return false;

    var valid = emailRegex.test(email);
    if(!valid)
        return false;

    // Further checking of some things regex can't handle
    var parts = email.split("@");
    if(parts[0].length>64)
        return false;

    var domainParts = parts[1].split(".");
    if(domainParts.some(function(part) { return part.length>63; }))
        return false;

    return true;
}