I found a bug on Mahoor13 answer, it's not working in loop so I've fixed it with this correction:
HTML:
<input type="email" id="eid" name="email_field" oninput="check(this)">
Javascript:
function check(input) {
if(input.validity.typeMismatch){
input.setCustomValidity("Dude '" + input.value + "' is not a valid email. Enter something nice!!");
}
else {
input.setCustomValidity("");
}
}
It will perfectly running in loop.