Get data from file using ajax

I’m trying to do this scenario .
If folder is empty then return false else return true .
To do that i tried this

function downloadExcel() {
// Mu folder path 
var folder="D:/output";
if (result.isConfirmed) {
                    $.ajax({
                    type: 'POST',
                    url: 'check_file.php',
                    data: {
                        folder: folder
                    },
                    cache: false,
                    success: function(result){
                        if(result==false)
                        {
                            Swal.fire(
                                    'execution success '
                            );
                        }
                        else
                        {
                            Swal.fire(
                                'extraction failed '
                            );  
                        }
                        
                },
                error: function(result){

                   console.log("Error request Ajax");
                } 
                });
                
                refresh();

            } else if (
                result.dismiss === Swal.DismissReason.cancel
            

my php file to render the data :: check_file.php

<?php
if (!empty($_POST["folder"])) {
$dir = $_POST['folder'];
}

if (is_dir_empty($dir)) {
echo "the folder is empty"; 
$result=false;

}else{
 echo "the folder is NOT empty";
 $result=true; 
}

return $result;


function is_dir_empty($dir) {
if (!is_readable($dir)) return null; 
return (count(scandir($dir)) == 2);
}

?> 

When i run my check_file.php the check if directory is empty or not works fine .

But when i try the the $result variable there something gone wrong about my code

The $result variable is always empty

>Solution :

1. You’re never echoing $result – and even if you did, echoing a boolean false doesn’t actually produce any visible output. Using return to end the main part of a script isn’t necessary, doesn’t really make much sense and certainly doesn’t produce any output.

2. The things you are echoing consist of neither true nor false, so obviously the JS code won’t match those either.

3. To allow the JS to detect a truth-y or false-y value accurately, it’s better to output numeric 0 or 1 than strings.

4. As an additional point, it would make sense not to try and use $dir unless it’s been populated.

This version should help you (note that if there’s no value in $_POST["folder"] it won’t output anything – you might want to add something extra to deal with that, but I’ll leave it up to you):

<?php
if (!empty($_POST["folder"])) 
{
  $dir = $_POST['folder'];
  $result;

  if (is_dir_empty($dir)) $result = 0; 
  else $result = 1;

  echo $result;
}

function is_dir_empty($dir) {
  if (!is_readable($dir)) return null; 
  return (count(scandir($dir)) == 2);
}
?>