Detailed explanation of the method of deleting empty folders based on recursion in php7

<?php
$path = &#39;d:/&#39;;
rmDir_1($path);
function rmDir_1($path) {
  $files = scandir($path);
// 删除当前目录和上一级目录
  foreach($files as $key => $file) {
    if ( $file == &#39;.&#39; || $file == &#39;..&#39;) {
      unset($files[$key]);
    }
  }
  if ($files) {
    foreach($files as $file) {
      if (is_dir($path . &#39;/&#39; . $file)) {
        //echo &#39;dir=&#39; . $path . &#39;/&#39; . $file . PHP_EOL;
        rmDir_1($path . &#39;/&#39; . $file);
      }
    }
  } else {
    //echo &#39;rmdir=&#39; . $path . PHP_EOL;
    rmdir($path);
  }
}
?>