1.31字节PHP随机显示头像

<?readfile(rand(0,5).'.jpg');?>

2.

<?php

$url='pic';

//图片地址，用相对路径

$files=array();

if($handle=opendir("$url")){

while(false!==($file=readdir($handle))){

if($file!="."&&$file!=".."){

if(substr($file,-3)=='gif'

substr($file,-3)=='jpg')$files[count($files)]=$file;

}

}

}

closedir($handle);

$random=rand(0,count($files)-1);

if(substr($files[$random],-3)=='gif')header("Content-type:image/gif");

elseif(substr($files[$random],-3)=='jpg')header("Content-type:image/jpeg");

readfile("$url/$files[$random]");

?>