Jquery AJAX post to PHP

Question

OK i've got my json string built but i'm not sure what to do next??

$('#submit').live('click',function(){ 

                var dataString = '[';
                    $('#items tr').not(':first').each(function(){
                        var index = $('#items tr').index(this);
                        var supp_short_code=$(this).closest('tr').find('.supp_short_code').text();
                        var project_ref=$(this).closest('tr').find('.project_ref').text();
                        var om_part_no=$(this).closest('tr').find('.om_part_no').text();
                        var description=$(this).closest('tr').find('.description').text();
                        var cost_of_items=$(this).closest('tr').find('.cost_of_items').text();
                        var cost_total=$(this).closest('tr').find('.cost_total').text();
                        dataString += '{"row":"' + index + '", "supp_short_code":"' + supp_short_code + '", "project_ref":"' + project_ref + '", "om_part_no":"' + om_part_no + '", "description":"' + description + '", "cost_of_items":"' + cost_of_items + '", "cost_total_td":"' + cost_total + '"}';
                    });
                    dataString += ']';

                $.ajax
                    ({
                    type: "POST",
                    url: "order.php",
                    data: dataString,
                    cache: false,
                    success: function()
                        {
                            alert("Order Submitted");
                        }
                    });
            });

In my php file i was attempting to write the dataString to a text file so i could see its coming through ok but nothing was in the text file!? Am i doing something wrong client side or PHP side, my php code:

<?php
    $stringData = $_POST['dataString']; 
    $myFile = "testFile.txt";
    $fh = fopen($myFile, 'w') or die("can't open file");
    fwrite($fh, $stringData);
    fclose($fh);
?>

Answer 1

This should do it:

...
$.ajax({
    type: "POST",
    url: "order.php",
    data: { 'dataString': dataString },
    cache: false,
    success: function()
        {
            alert("Order Submitted");
        }
    });

You may try to verify:

<?php
    $stringData = $_POST['dataString']; 
    echo $stringData;
?>