php文件在线压缩程序类

时间：2015-01-23 来源：西部数据作者：西部数据

提供一款超完美的php文件在线压缩程序,原理很简单就是把文件以二进制形式保存了,以前用过利用rar的内核程序,这是php自带的压缩功能,实例代码如下:

set_time_limit(0);

class phpzip{

    var $file_count = 0 ;

    var $datastr_len   = 0;

    var $dirstr_len = 0;

    var $filedata = ''; //该变量只被类外部程序访问

    var $gzfilename;

    var $fp;

    var $dirstr='';

    /*

    返回文件的修改时间格式.

    只为本类内部函数调用.

    */

    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;

        }

        return (($timearray['year'] - 1980) << 25) | ($timearray['mon'] << 21) | ($timearray['mday'] << 16) |

               ($timearray['hours'] << 11) | ($timearray['minutes'] << 5) | ($timearray['seconds'] >> 1);

    }

    /*

    初始化文件,建立文件目录,

    并返回文件的写入权限.

    */

    function startfile($path = 'faisun.zip'){

       $this->gzfilename=$path;

       $mypathdir=array();

       do{

        $mypathdir[] = $path = dirname($path);

       }while($path != '.');

       @end($mypathdir);

       do{

        $path = @current($mypathdir);

        @mkdir($path);

       }while(@prev($mypathdir));

       if($this->fp=@fopen($this->gzfilename,"w")){

        return true;

       }

       return false;

    }

    /*

    添加一个文件到 zip 压缩包中.

    */



function addfile($data, $name){

        $name     = str_replace('\', '/', $name);

    if(strrchr($name,'/')=='/') return $this->adddir($name);

        $dtime    = dechex($this->unix2dostime());

        $hexdtime = 'x' . $dtime[6] . $dtime[7]

                  . 'x' . $dtime[4] . $dtime[5]

                  . 'x' . $dtime[2] . $dtime[3]

                  . 'x' . $dtime[0] . $dtime[1];

        eval('$hexdtime = "' . $hexdtime . '";');

        $unc_len = strlen($data);

        $crc     = crc32($data);

        $zdata   = gzcompress($data);

        $c_len   = strlen($zdata);

        $zdata   = substr(substr($zdata, 0, strlen($zdata) - 4), 2);

    //新添文件内容格式化:

        $datastr = "PK";

        $datastr .= "";            // ver needed to extract

        $datastr .= "";            // gen purpose bit flag

        $datastr .= "";            // compression method

        $datastr .= $hexdtime;             // last mod time and date

        $datastr .= pack('v', $crc);             // crc32

        $datastr .= pack('v', $c_len);           // compressed filesize

        $datastr .= pack('v', $unc_len);         // uncompressed filesize

        $datastr .= pack('v', strlen($name));    // length of filename

        $datastr .= pack('v', 0);                // extra field length

        $datastr .= $name;

        $datastr .= $zdata;

        $datastr .= pack('v', $crc);                 // crc32

        $datastr .= pack('v', $c_len);               // compressed filesize

        $datastr .= pack('v', $unc_len);             // uncompressed filesize

    fwrite($this->fp,$datastr); //写入新的文件内容

    $my_datastr_len = strlen($datastr);

    unset($datastr);

    //新添文件目录信息

        $dirstr = "PK";

        $dirstr .= "";                // version made by

        $dirstr .= "";                // version needed to extract

        $dirstr .= "";                // gen purpose bit flag

        $dirstr .= "";                // compression method

        $dirstr .= $hexdtime;                 // last mod time & date

        $dirstr .= pack('v', $crc);           // crc32

        $dirstr .= pack('v', $c_len);         // compressed filesize

        $dirstr .= pack('v', $unc_len);       // uncompressed filesize

        $dirstr .= pack('v', strlen($name) ); // length of filename

        $dirstr .= pack('v', 0 );             // extra field length

        $dirstr .= pack('v', 0 );             // file comment length

        $dirstr .= pack('v', 0 );             // disk number start

        $dirstr .= pack('v', 0 );             // internal file attributes

        $dirstr .= pack('v', 32 );            // external file attributes - 'archive' bit set

        $dirstr .= pack('v',$this->datastr_len ); // relative offset of local header

        $dirstr .= $name;

    $this->dirstr .= $dirstr; //目录信息

    $this -> file_count ++;

    $this -> dirstr_len += strlen($dirstr);

    $this -> datastr_len += $my_datastr_len;

    }

    function adddir($name){

       $name = str_replace("\", "/", $name);

       $datastr = "PK ";

       $datastr .= pack("v",0).pack("v",0).pack("v",0).pack("v", strlen($name) );

       $datastr .= pack("v", 0 ).$name.pack("v", 0).pack("v", 0).pack("v", 0);

       fwrite($this->fp,$datastr); //写入新的文件内容

       $my_datastr_len = strlen($datastr);

       unset($datastr);

       $dirstr = "PK ";

       $dirstr .= pack("v",0).pack("v",0).pack("v",0).pack("v", strlen($name) );

       $dirstr .= pack("v", 0 ).pack("v", 0 ).pack("v", 0 ).pack("v", 0 );

       $dirstr .= pack("v", 16 ).pack("v",$this->datastr_len).$name;

       $this->dirstr .= $dirstr; //目录信息

       $this -> file_count ++;

       $this -> dirstr_len += strlen($dirstr);

       $this -> datastr_len += $my_datastr_len;

    }//开源代码phpfensi.com

    function createfile(){

       //压缩包结束信息,包括文件总数,目录信息读取指针位置等信息

       $endstr = "PK" .

          pack('v', $this -> file_count) .

          pack('v', $this -> file_count) .

          pack('v', $this -> dirstr_len) .

          pack('v', $this -> datastr_len) .

          "";

       fwrite($this->fp,$this->dirstr.$endstr);

       fclose($this->fp);

    }

}