<script type="text/javascript">
$(document).ready(function () {
$("#submit").click(function () {
var login = $("#login").val();
var password = $("#password").val();
var submit = $("#submit").val();
$.post('server.php', {login:login, password:password, submit:submit}, function (data) {
$("#block").text(data);
});
});
});
</script>
<?php
if (filter_has_var(INPUT_POST, 'submit')) {
if (empty($_POST['login'])) {
?>
<div class="alert alert-danger">
Вы не ввели логин!
</div>
<?php
die();
}
}