Detailed explanation of example code for deleting read files and obtaining file images in PHP

unlink("tmp/test.txt");

$content=str_replace("\n","",$content);
echo $content;

$content=str_replace（array("\n","\r"),"",$content);

$content=preg_replace("/\s/","",$content);

$content=trim($content);

$dir = "message/"; // 文件夹的名称
if (is_dir($dir)){
  if ($dh = opendir($dir)){
    while (($file = readdir($dh)) !== false){
      echo "文件名: $file <br>";
    }
    closedir($dh);
  }
}

<?php
$handle = opendir(&#39;images/&#39;); //当前目录
  while (false !== ($file = readdir($handle))) { //遍历该php文件所在目录
   list($filesname,$kzm)=explode(".",$file);//获取扩展名
    if($kzm=="gif" or $kzm=="jpg" or $kzm=="JPG") { //文件过滤
     if (!is_dir(&#39;./&#39;.$file)) { //文件夹过滤
      $array[]=$file;//把符合条件的文件名存入数组
      $i++;//记录图片总张数
      }
     }
  }
 print_r($array);
?>