为什么返回不起作用，但echo在这个jquery中使用php脚本

Question

In this script, using php's return will not work, whereas echo will. Thing is, if I use echo, and someone where to access the page directly, they would be able to see the output without the formatting.

<script type="text/javascript">
$(function() {

    $('.callAppend').click(function() {
             $.ajax({
                type: 'GET',
                url:  'recent.php',
                dataType:'HTML',
                cache:false,

                success: function(data){
                console.log(data);

                //}       

              },

            });    

        return false;
    });
});
</script>

This the php script

<?php
$feedback = 'Hello this is the php page';

return $feedback; //Use echo, and all works fine.
?>

Answer 1

return is used for returning a value from a function to another piece of PHP code.

jQuery is not part of the execution of the PHP code on the server, so it has no idea what is really going on server side. jQuery is waiting for the rendered server response, which is what echo provides.

---

This SO answer provides a solution to only allow an AJAX script to be called by that type of request: Prevent Direct Access To File Called By ajax Function

Even though it is checking for 'XMLHttpRequest', someone could make this type of request from something else other than you weboage.