$_GET PHP form variable AJAX check 404 then submit form - php

Question

I have a form on a page that accepts an 'ID', user inputs ID eg; 1026
The form submits to the same page ajax grabs the ID checks it against another site. I need to be able to let the form post if the response is NOT a 404 error and $_GET is true.
Heres what I have
<script>
$(document).ready(function(){
$('form#getid').submit(function(){
var theid = $('input#id').val();
var dataString = "id=" + theid;
$.ajax({
type: "POST",
data: dataString,
success: function(response, status, xhr){
if(status=="success") {
$("#err-404").html(response);
}
else { alert(status+ ' - '+ xhr.status); }
}
}
});
});
return false;
});
</script>
My form
<form id="getid" action="">
<input type="text" name="id" />
<input type="submit" class="button" value="Go">
<div class="error" id="err-404"></div>
I think im on the right track, just not sure how to put it all together.

Answer 1

Firstly, if you don't have to use a string for your data, don't. You can use an array like so:
$.ajax({
type: "POST",
data: {'id': theid },
Which is cleaner and more maintainable.
As for your question, your code is a little unclear, but what you probably should do is return false at the end of the submit() event to prevent the form from submitting, and then in the AJAX event, if it's cleared for submission, do a $('#getid').submit(). You may have to set some kind of flag (a hidden input or a data attribute) that you check on to avoid the AJAX-triggered submit from checking again, resulting in an infinite loop.
A note here: 404s should cause the error() callback in the AJAX handler to fire, so a 404 won't trigger the success callback you have set up.