通过datatables ajax请求发送POST数据

Question

I'm trying to make a simple ajax call in datatables that is reliant on a post array of IDs from a previous page's form. I am getting the error :

Invalid JSON Response

which tells me that my returned json array is probably empty or something and I have a feeling it has to do with the POST data not being sent to my php/sql external script on which ajax is requesting the data from.

I'm not sure how to test it as I don't know how to include the $_POST data in the URL to my external php page to outright trigger the script.

Heres my current datatables init and php from the results page:

<?php
include_once('../functions.php');
sec_session_start();
print_r($_POST['post_id']); <-- making sure the post data made it this far
?>

<script type="text/javascript">  
    $(document).ready(function() {
    var compTable = $('#compTab').dataTable({
        "processing": true,
        "serverSide": true,
        "ajax": {
            "url": "baddebt_ext_sql.php",
            "type": "POST",
            "dataType": 'json',
            "data": {"post_id": $_POST['post_id']}
        },                              
        "Columns": [
            { "data": "provider_num" },
            { "data": "provider_name"},
            { "data": "261_total_bed_debts", "sClass": "rightAlign" },
            { "data": "271_medicare_bad_debts", "sClass": "rightAlign" },
            { "data": "281_non_medicare_bad_debts", "sClass": "rightAlign" },
            { "data": "1_cost_to_charge_ratio", "sClass": "rightAlign" },
            { "data": "291_cost_of_non_mcr_bad_debts", "sClass": "rightAlign" }
        ],
        "scrollY":        "600px",
        "scrollCollapse": true,
        "paging":         false,
        "order": [[ 2, "desc" ]],
        "oLanguage": { "sSearch": "Filter All Fields By:" },
        "Dom": '<"clear">lfrtipT',
        "TableTools": {
              "sSwfPath" : "../php/tabletools/swf/copy_csv_xls_pdf.swf" }
    });

and here is my SQL:

<?php
include_once('../link_costreport_2013.php');
if(isset($_POST['post_id'])){
    $in = $_POST['post_id']; <-- THIS IS WHERE THE POST DATA IS SUPPOSED TO BE RECEIVED
}
$data = array();
foreach ($in as $id){
    $query = $link->prepare("SELECT id,provider_num, provider_name, 261_total_bed_debts, 271_medicare_bad_debts, 281_non_medicare_bad_debts, 1_cost_to_charge_ratio, 291_cost_of_non_mcr_bad_debts
                FROM `s10`
                            WHERE `id` = :id");
    $query->bindParam(':id', $id, PDO::PARAM_INT);
    $query->execute();
    $results = $query->fetch(PDO::FETCH_ASSOC);
    $results['261_total_bed_debts'] = "\$".number_format($results['261_total_bed_debts']);
    $results['271_medicare_bad_debts'] = "\$".number_format($results['271_medicare_bad_debts']);
    $results['281_non_medicare_bad_debts'] = "\$".number_format($results['281_non_medicare_bad_debts']);
    $results['291_cost_of_non_mcr_bad_debts'] = "\$".number_format($results['291_cost_of_non_mcr_bad_debts']);
    $results['provider_name'] = "<a id='".$results['id']."' data-toggle='modal' href='#provmodal' class='push'>".$results['provider_name']."</a>";
    $data[] = $results;
}
echo json_encode($data);

If anyone knows how I can get my json array from this script without utilizing the previous pages $_POST data it is supposed to send, then I will gladly post it as well.

Basically I'm just wondering if there are any steps I am missing when it comes to feeding this array of IDs through my datatables ajax query and into the second page's sql. ( an example of the post_id array is like this: Array ( [0] => 299 [1] => 1555 [2] => 3539 ) )

Answer 1

Diagnosing this problem is pretty easy. Simply right mouse click and "inspect element" then choose the Network tab. Toggle the transaction as you would in your interface. You'll see a new network transaction in the network tab.

Click on that new network transaction -- it should have the address that you're defining in the ajax call. The headers will show the variables you sent via post, response will show what the server returned.

The error is indicating that your response will fail if you paste the payload into jslint.com and evaluate it. What the cause of that failure is will require more details than you've provided.

In the ajax example you use, "data" is the data that's being sent to the server. To send a large amount of data in that post, I'd enclose your inputs in a form tag, then do a $.serialize or $.serializeArray on that form. You can then send that serialized data over as a variable via the data attribute, where it will be posted to your server. From there, just deal with the resulting post variables via PHP.

Please do update your code to use 1.10 API variables. Support for the old ones will be deprecated in the future versions.