Analyzing Folder Contents in PHP

Suppose we have a folder dir, containing both files and folders.

Let's get an array of names from this folder:

php<?php
  $files = array_diff(scandir('dir'), ['..', '.']);
?>

Let's check for each name whether it is a file or a folder:

php<?php
  $files = array_diff(scandir('dir'), ['..', '.']);
  
  foreach ($files as $file) {
    echo $file;
    var_dump(is_file('dir/' . $file));
  }
?>

Please note that the name of the folder we are scanning is written in two places in the code. This is not very convenient. Let's move this name to a separate variable:

php<?php
  $dir = 'dir';
  $files = array_diff(scandir($dir), ['..', '.']);
  
  foreach ($files as $file) {
    echo $file;
    var_dump(is_file($dir. '/' . $file));
  }
?>

Now let's output the contents of all files to the screen:

php<?php
  $dir = 'dir';
  $files = array_diff(scandir($dir), ['..', '.']);
  
  foreach ($files as $file) {
    if (is_file($dir. '/' . $file)) {
      echo file_get_contents($dir. '/' . $file);
    }
  }
?>

It can be noticed that the path to the file is calculated twice. Let's move it to a separate variable:

php<?php
  $dir = 'dir';
  $files = array_diff(scandir($dir), ['..', '.']);
  
  foreach ($files as $file) {
    $path = $dir. '/' . $file; // file path
    
    if (is_file($path)) {
      echo file_get_contents($path);
    }
  }
?>