问如何在wordpress中使用ajax jquery进行更新？

EN

function ajaxFunction(str,id) {

    var payment_selected = str;
    var id=id;
    var queryString = '&id_took='+id+'&sel='+payment_selected;        
    var data = {
        'action' : 'my_action',
        'payment_selected': payment_selected,
        'id'    : id            
    };

    jQuery.post(admin_url("admin-ajax.php"), data, function(response) {
    jQuery("#status").html(response);
    });
}

/* this is a php file , i used in the plugin where below html form appears  */
<?php

 add_action( 'wp_ajax_nopriv_my_action', 'my_action' );
    add_action( 'wp_ajax_my_action', 'my_action' );

function my_action() {    
     global $wpdb;
     $id_selected = $_POST['payment_selected']; 
     $id = $_POST['id'];
     $table_name_payment = $wpdb->prefix . "online_booking_system_model";    
     $result_pay =  $wpdb->query($wpdb->prepare("UPDATE $table_name_payment SET payment_status = $id_selected WHERE id=$id"));
     echo "success";

?>
/* this is  the html file */
 foreach ($rows as $row) { ?>  
 <table>
  <td><?php echo $row->payment_status; ?></td>
<select  name='payment_select' id="payment_select" onchange="ajaxFunction(this.value,<?php echo $row->id ?>)">   
                            <option value="Payment Due">Payment Due</option>
                        <option value="Payment completed">Payment Completed</option>
                        </select> 
                         <?php } ?>
                         <table>
                         <div id="status"></div>