codice:
<!doctype html>
 
<html lang="en">
<head>
  <meta charset="utf-8">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>
$(document).ready(function () {   
    $( ".spedisciaPHP" ).click(function() {
 
        var thisnum = $('.datasend').text();
 
            $.post("receiving.php",
            {
                thisnum: thisnum
            },
           
            function(data, status){
                if(status == 'success'){
                    var res = data.trim();
                    alert(res);
                }
             });
               
    });
 
});
</script>
  <title></title>
</head>
codice:
<body>
<div class="datasend"><?php echo rand(1,9999999)?></div>
<br><br><br><br>
<div class="spedisciaPHP"><b>cliccami invierò il numero a receiving.php</b></div>
 
</body>
</html>