CODE EXAMPLE FOR JAVASCRIPT

SMTP js

// Include this script:
var Email = { send: function (a) { return new Promise(function (n, e) { a.nocache = Math.floor(1e6 * Math.random() + 1), a.Action = "Send"; var t = JSON.stringify(a); Email.ajaxPost("https://smtpjs.com/v3/smtpjs.aspx?", t, function (e) { n(e) }) }) }, ajaxPost: function (e, n, t) { var a = Email.createCORSRequest("POST", e); a.setRequestHeader("Content-type", "application/x-www-form-urlencoded"), a.onload = function () { var e = a.responseText; null != t && t(e) }, a.send(n) }, ajax: function (e, n) { var t = Email.createCORSRequest("GET", e); t.onload = function () { var e = t.responseText; null != n && n(e) }, t.send() }, createCORSRequest: function (e, n) { var t = new XMLHttpRequest; return "withCredentials" in t ? t.open(e, n, !0) : "undefined" != typeof XDomainRequest ? (t = new XDomainRequest).open(e, n) : t = null, t } };
// Or:
// <script src="https://smtpjs.com/v3/smtp.js"></script>

// Then send emails:
Email.send({
    Host : "smtp.yourisp.com",
    Username : "username",
    Password : "password",
    To : 'them@website.com',
    From : "you@isp.com",
    Subject : "This is the subject",
    Body : "And this is the body"
}).then(
  message => alert(message)
);

// More options -> https://smtpjs.com/