PHP数组提交给ajax

Question

I'm not sure if this question has been asked before, so please note if it's duplicate.

The top line is a PHP merged array that I'm trying to send in AJAX to another page.

I'm having trouble finding what goes in the "?" or how to format it.

<?php $_SESSION['pdfData'] = array_merge_recursive($count, $qty); ?>

$.ajax({ 
    type: "POST",
    url: "indexMenu-sm-pdf.php",
    data: { 
            ? 
        },
    dataType: "JSON", 
    success: function(data){
        console.log("Good.");
    },
        error: function(jqXHR, textStatus, errorThrown) {
        console.log(textStatus, errorThrown);
    } 
});

I understand that the built-in function json_encode() but i lack the know-how. And I've been reading about serialization. Is one better than the other?

My main questions are:
What goes into the "?" as $_Session['pdfData'] can not be sent.
And
Is there a difference is using json_encode vs. serialization for this issue?

</div>

Answer 1

It should be something like this:

$.ajax({ 
    type: "POST",
    url: "indexMenu-sm-pdf.php",
    data: { 
            paramName: <?php echo json_encode($_SESSION['pdfData']) ?>
        },
    dataType: "JSON", 
    success: function(data){
        console.log("Good.");
    },
        error: function(jqXHR, textStatus, errorThrown) {
        console.log(textStatus, errorThrown);
    } 
});

Replace paramName with the name of the $_POST parameter that indexMenu-sm-pdf.php is expecting to get the PDF data from. json_encode() will output the contents of the session variable in the form of a Javascript literal.