function list_files($dir)
{
	if(is_dir($dir))
  	{
  		if($handle = opendir($dir))
  		{
  			while(($file = readdir($handle)) !== false)
  			{
  				if($file != "." && $file != ".." && $file != "Thumbs.db")
  				{
  					echo '<a target="_blank" href="'.$dir.$file.'">'.$file.'</a><br>'."\n";
  				}
  			}
  			closedir($handle);
  		}
	}
}

function is_valid_email($email, $test_mx = false)
{
	if(eregi("^([_a-z0-9-]+)(\.[_a-z0-9-]+)*@([a-z0-9-]+)(\.[a-z0-9-]+)*(\.[a-z]{2,4})$", $email))
		if($test_mx)
		{
			list($username, $domain) = split("@", $email);
			return getmxrr($domain, $mxrecords);
		}
		else
			return true;
	else
		return false;
}

List content of directory

PHP