生成zip压缩包，支持多目录，thinkphp

<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2014 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: 麦当苗儿 <[e-mail]> <http://www.zjzit.cn>
// +----------------------------------------------------------------------
namespace Think;
class PHPZip{
    var $dirInfo = array("0","0");
    var $rootDir = '';
    var $datasec = array();
    var $ctrl_dir = array();
    var $eof_ctrl_dir = "\x50\x4b\x05\x06\x00\x00\x00\x00";
    var $old_offset = 0;

    function downloadZip(){
        createZip($dir, $zipfilename, true);
    }
    function createZip($dir, $zipfilename, $autoDownload = false){
        if (@function_exists('gzcompress')){
            @set_time_limit("0");
            if (is_array($dir)){
                $fd = fopen ($dir, "r");
                $fileValue = fread ($fd, filesize ($filename));
                fclose ($fd);
                if (is_array($dir)) $filename = basename($dir);
                $this -> addFile($fileValue, "$filename");
            }else{
                $this->dirTree($dir,$dir);
            }

            $zipfilenametemp = time().$zipfilename;
            $out = $this -> filezip();
            $fp = fopen($zipfilenametemp, "w");
            fwrite($fp, $out, strlen($out));
            fclose($fp);
            $filesize = filesize($zipfilenametemp);

            if ($filesize < 104857600) {
                if($autoDownload){
                    header("Content-type: application/octet-stream");
                    header("Content-disposition: attachment; filename=".$zipfilename);
                }
                echo $this -> filezip();
            }else{
                echo "create zip error!";
            }
            unlink($zipfilenametemp);
        }
    }
    //get dir tree..
    function dirTree($directory,$rootDir){
        global $_SERVER,$dirInfo,$rootDir;

        $fileDir=$rootDir;
        $myDir=dir($directory);
        while($file=$myDir->read()){
            if(is_dir("$directory/$file") and $file!="." and $file!=".."){
                $dirInfo[0]++;
                $rootDir ="$fileDir$file/";

                $this -> addFile('', "$rootDir");

                //go on n's folders
                $this->dirTree("$directory/$file",$rootDir);
            }else{
                if($file!="." and $file!=".."){
                    $dirInfo[1]++;
                    //$fd = fopen ("$directory/$file", "r");
                    $fileValue = file_get_contents("$directory/$file");
                    //fclose ($fd);
                    $this -> addFile($fileValue, "$fileDir$file");
                }
            }
        }
        $myDir->close();
    }
    function unix2DosTime($unixtime = 0) {
        $timearray = ($unixtime == 0) ? getdate() : getdate($unixtime);

        if ($timearray['year'] < 1980) {
            $timearray['year'] = 1980;
            $timearray['mon'] = 1;
            $timearray['mday'] = 1;
            $timearray['hours'] = 0;
            $timearray['minutes'] = 0;
            $timearray['seconds'] = 0;
        } // end if

        return (($timearray['year'] - 1980) << 25) | ($timearray['mon'] << 21) | ($timearray['mday'] << 16) |
        ($timearray['hours'] << 11) | ($timearray['minutes'] << 5) | ($timearray['seconds'] >> 1);
    }
    function addFile($data, $name, $time = 0){
        $name = str_replace('\\', '/', $name);

        $dtime = dechex($this->unix2DosTime($time));
        $hexdtime = '\x' . $dtime[6] . $dtime[7]
            . '\x' . $dtime[4] . $dtime[5]
            . '\x' . $dtime[2] . $dtime[3]
            . '\x' . $dtime[0] . $dtime[1];
        eval('$hexdtime = "' . $hexdtime . '";');

        $fr = "\x50\x4b\x03\x04";
        $fr .= "\x14\x00"; // ver needed to extract
        $fr .= "\x00\x00"; // gen purpose bit flag
        $fr .= "\x08\x00"; // compression method
        $fr .= $hexdtime; // last mod time and date

// "local file header" segment
        $unc_len = strlen($data);
        $crc = crc32($data);
        $zdata = gzcompress($data);
        $c_len = strlen($zdata);
        $zdata = substr(substr($zdata, 0, strlen($zdata) - 4), 2); // fix crc bug
        $fr .= pack('V', $crc); // crc32
        $fr .= pack('V', $c_len); // compressed filesize
        $fr .= pack('V', $unc_len); // uncompressed filesize
        $fr .= pack('v', strlen($name)); // length of filename
        $fr .= pack('v', 0); // extra field length
        $fr .= $name;

// "file data" segment
        $fr .= $zdata;

// "data descriptor" segment (optional but necessary if archive is not
// served as file)
        $fr .= pack('V', $crc); // crc32
        $fr .= pack('V', $c_len); // compressed filesize
        $fr .= pack('V', $unc_len); // uncompressed filesize

// add this entry to array
        $this -> datasec[] = $fr;
        $new_offset = strlen(implode('', $this->datasec));

// now add to central directory record
        $cdrec = "\x50\x4b\x01\x02";
        $cdrec .= "\x00\x00"; // version made by
        $cdrec .= "\x14\x00"; // version needed to extract
        $cdrec .= "\x00\x00"; // gen purpose bit flag
        $cdrec .= "\x08\x00"; // compression method
        $cdrec .= $hexdtime; // last mod time & date
        $cdrec .= pack('V', $crc); // crc32
        $cdrec .= pack('V', $c_len); // compressed filesize
        $cdrec .= pack('V', $unc_len); // uncompressed filesize
        $cdrec .= pack('v', strlen($name) ); // length of filename
        $cdrec .= pack('v', 0 ); // extra field length
        $cdrec .= pack('v', 0 ); // file comment length
        $cdrec .= pack('v', 0 ); // disk number start
        $cdrec .= pack('v', 0 ); // internal file attributes
        $cdrec .= pack('V', 32 ); // external file attributes - 'archive' bit set

        $cdrec .= pack('V', $this -> old_offset ); // relative offset of local header
        $this -> old_offset = $new_offset;

        $cdrec .= $name;

// optional extra field, file comment goes here
// save to central directory
        $this -> ctrl_dir[] = $cdrec;
    }
    function filezip(){
        $data = implode('', $this -> datasec);
        $ctrldir = implode('', $this -> ctrl_dir);

        return
            $data .
            $ctrldir .
            $this -> eof_ctrl_dir .
            pack('v', sizeof($this -> ctrl_dir)) . // total # of entries "on this disk"
            pack('v', sizeof($this -> ctrl_dir)) . // total # of entries overall
            pack('V', strlen($ctrldir)) . // size of central dir
            pack('V', strlen($data)) . // offset to start of central dir
            "\x00\x00"; // .zip file comment length
    }
}
?>