Zip multiple database PDF blob files

问题

I have a database table that contains numerous PDF blob files. I am attempting to combine all of the files into a single ZIP file that I can download and then print.

Please help!

<?php 
    include '../config.php';
    include '../connect.php';

    $session = $_GET['session'];

    $query = "SELECT $tbl_uploads.username, $tbl_uploads.description,
                     $tbl_uploads.type, $tbl_uploads.size, $tbl_uploads.content,
                     $tbl_members.session
    FROM $tbl_uploads
    LEFT JOIN $tbl_members
    ON $tbl_uploads.username = $tbl_members.username
    WHERE $tbl_members.session = '$session'";
    $result = mysql_query($query) or die('Error, query failed');


    $files = array();
    while(list($username, $description, $type, $size, $content) = 
     mysql_fetch_array($result)) {

        $files[] = "$username-$description.pdf";
    }

    $zip = new ZipArchive; 
    $zip->open('file.zip', ZipArchive::CREATE); 
    foreach ($files as $file) { 
      $zip->addFile($file); 
    } 
    $zip->close(); 

    header('Content-Type: application/zip'); 
    header('Content-disposition: attachment; filename=filename.zip'); 
    header('Content-Length: ' . filesize($zipfilename)); 
    readfile($zipname); 

    exit();


    ?>

回答1:

Your PDF data is stored in the database in BLOB fields, I don't see you putting this data in a file. So your ZIP will not contain any files because you don't add real existing files to it.

This is what you are currently doing:

Reading your data from the database
Creating an array of filenames
Creating a ZIP of filenames that might not exist

This what you should do:

Reading your data from the database
Creating an array of filenames
Write your BLOB data into that files
Creating a ZIP of files that exist

Example:

    $files = array();
    while(list($username, $description, $type, $size, $content) = 
     mysql_fetch_array($result)) {
        $files[] = "$username-$description.pdf";

        // write the BLOB Content to the file
        if ( file_put_contents("$username-$description.pdf", $content) === FALSE ) {
          echo "Could not write PDF File";
        }
    }

What you should do if that works for you:

Write the files in a temporary folder (maybe with some help of http://php.net/tempnam) somewhere else and maybe remove them after your archiving process.

There is also a second problem in your code, you use $zipfilename for calculating the content-length and $zipname to read the file and no variable to create the zip. Since $zipfilename and $zipname is not defined, this won't work.

You should define $zipfilename with a ZIP filename and also use that same variable when creating the zip file.

Example:

    // a temp filename containing the current unix timestamp
    $zipfilename = 'temp_' . time() . '.zip';

    $zip->open($zipfilename, ZipArchive::CREATE);
    foreach ($files as $file) { 
       $zip->addFile($file); 
    } 
    $zip->close(); 

    header('Content-Type: application/zip'); 
    header('Content-disposition: attachment; filename=filename.zip'); 
    header('Content-Length: ' . filesize($zipfilename)); 
    readfile($zipfilename);

回答2:

pdftk will merge multiple PDF files, as well as PDFsam..

来源：https://stackoverflow.com/questions/3024765/zip-multiple-database-pdf-blob-files

标签

php

mysql

database

zip

blob