php 读取目录所有文件信息dir（）

<?php
set_time_limit(0);
function tree($directory)
{
$mydir=dir($directory);
echo "<ul> ";
while($file=$mydir->read()){
if((is_dir("$directory/$file")) AND ($file!=".") AND ($file!=".."))
{
        echo "<li><font color=&#39;#ff00cc&#39;><b>$file</b></font></li> ";
tree("$directory/$file");
}
else
        {
echo "<li>$file</li> ";
        }
}
echo "</ul>
";
$mydir->close();
}
//start the program
echo "<h2>目录为粉红色</h2>
";
tree(".");
?>