Question

$.post('includes/script.php', $(this).serialize(), function(data) {
    $('body').append(data);
});

alert ($('#new').length)

php script is <php echo "<div id="new">text</div>" ?>

it alerts 0, so it can’t see new div.

How can you make it see new div?

Answer 1

You have to wait till your post is done before you can check the length. Do something like this:

$.post('includes/script.php', $(this).serialize(), function(data) {
    var newItem = $(data).appendTo('body');
    alert (newItem.length);
});