JQuery-AJAX: No further request after timeout and delay in form post

I got a form containing multiple checkboxes. This form shall be sent to the server to receive appropriate results from a server side script.

This is already working.

What I would achieve now:

1) Implementing a timeout: This is already working, but as soon as a timeout occurs, a new request is not working anymore.

2) Implementing a delay in requesting results: A delay shall be implemented so that not every checkbox is resulting in a POST request.

This is what I have right now:

function update_listing() {

    // remove postings from table
    $('.tbl tbody').children('tr').remove();

    // get the results through AJAX
    $.ajax({
                    type: "POST",
                    url: "http://localhost/hr/index.php/listing/ajax_csv", 
                    data: $("#listing_form").serialize(),
                    timeout: 5000,
                    success: function(data) {
                                    $(".tbl tbody").append(data);
                                },
                    error: function(objAJAXRequest, strError) {
                                    $(".tbl tbody").append("<tr><td>failed " + strError + "</td></tr&g开发者_如何学Got;");
                                }
                    });

    return true;

}

Results are for now passed as HTML table rows - I will transform them to CSV/JSON in the next step.

Thanks so much for your advice.

For the delay:

(function () {

var timeout;

function update_listing() {

    // remove postings from table
    clearTimeout(timeout);
    timeout = setTimeout(function () {

    $('.tbl tbody').children('tr').remove();

    // get the results through AJAX
    $.ajax({
        type: "POST",
        url: "http://localhost/hr/index.php/listing/ajax_csv", 
        data: $("#listing_form").serialize(),
        timeout: 5000,
        success: function(data) {
            $(".tbl tbody").append(data);
        },
        error: function(objAJAXRequest, strError) {
           $(".tbl tbody").append("<tr><td>failed " + strError + "</td></tr>");
        }
    });

    }, 1000); // 1 second?    

    return true;

}
}());

This will wait a second until making the AJAX request. What do you mean with regards to "as soon as a timeout occurs, a new request is not working anymore.". If you want to trigger another request if one fails, just call update_list() again (but note that the 1-second delay will be in effect).