Zip a folder (include itself).
Usage:
  HZip::zipDir('/path/to/sourceDir', '/path/to/out.zip');

<?php
class HZip
{
  /**
   * Add files and sub-directories in a folder to zip file.
   * @param string $folder
   * @param ZipArchive $zipFile
   * @param int $exclusiveLength Number of text to be exclusived from the file path.
   */
  private static function folderToZip($folder, &$zipFile, $exclusiveLength) {
    $handle = opendir($folder);
    while (false !== $f = readdir($handle)) {
      if ($f != '.' && $f != '..') {
        $filePath = "$folder/$f";
        // Remove prefix from file path before add to zip.
        $localPath = substr($filePath, $exclusiveLength);
        if (is_file($filePath)) {
          $zipFile->addFile($filePath, $localPath);
        } elseif (is_dir($filePath)) {
          // Add sub-directory.
          $zipFile->addEmptyDir($localPath);
          self::folderToZip($filePath, $zipFile, $exclusiveLength);
        }
      }
    }
    closedir($handle);
  }

  /**
   * Zip a folder (include itself).
   * Usage:
   *   HZip::zipDir('/path/to/sourceDir', '/path/to/out.zip');
   *
   * @param string $sourcePath Path of directory to be zip.
   * @param string $outZipPath Path of output zip file.
   */
  public static function zipDir($sourcePath, $outZipPath)
  {
    $pathInfo = pathInfo($sourcePath);
    $parentPath = $pathInfo['dirname'];
    $dirName = $pathInfo['basename'];

    $z = new ZipArchive();
    $z->open($outZipPath, ZIPARCHIVE::CREATE);
    $z->addEmptyDir($dirName);
    self::folderToZip($sourcePath, $z, strlen("$parentPath/"));
    $z->close();
  }
}
?>

With PHP 5.6+, you may come up with theses errors.

Warning: Unknown: Cannot destroy the zip context in Unknown on line 0

Warning: ZipArchive::close(): Can't remove file: No such file or directory in xxxx.php on line xx

Examples

Warning: Unknown: Cannot destroy the zip context in Unknown on line 0

<?php         
    $za = new ZipArchive;
    $za->open('51-n.com.zip',ZipArchive::CREATE|ZipArchive::OVERWRITE);
?>

Warning: ZipArchive::close(): Can't remove file: No such file or directory in xxxx.php on line xx

<?php         
    $za = new ZipArchive;
    $za->open('51-n.com.zip',ZipArchive::CREATE|ZipArchive::OVERWRITE);
    $za->close();
?>

It happens when the zip archive is empty.
Your zip archive will not be saved on disk unless it has at least one file. What's more, when ZipArchive::OVERWRITE is applied, if there exists a file with the same name, it will be removed after ZipArchive::open() is called.

So, don't forget to put at least one file to your zip archive.

<?php         
    $za = new ZipArchive;
    $za->open('51-n.com.zip',ZipArchive::CREATE|ZipArchive::OVERWRITE);
    $za->addFromString('wuxiancheng.cn.txt','yes');
    $za->close();
?>

A modern way to zip a folder recursivly is using the DirectoryIterator. I use this little class:

<?php
class MakeZip
{
  private ZipArchive $zipArchive;
  private int $startPathLength; // chars to remove from the start for the stored entity

  public function __construct(
    string $zipArchivename,
    public readonly string $startPath,
    public readonly mixed $convert_function,
  )
  {
    $this->zipArchive = new \ZipArchive;
    $this->zipArchive->open($zipArchivename, ZipArchive::CREATE);
    $this->startPathLength = strlen($this-> startPath);

    $this-> zipDir($startPath);
  }
  public function __destruct()
  {
    $this-> zipArchive-> close();
  }

  /**
   * Add files and sub-directories in a folder to zip file.
   * @param string $folder
   * @param ZipArchive $zipFile
   * @param int $exclusiveLength Number of text to be exclusived from the file path.
   */
  private function zipDir($folder)
  {
    echo $folder . '<br>' . PHP_EOL;
    foreach (new \DirectoryIterator($folder) as $f) {
      if ($f->isDot())
        continue; //skip . ..
      if ($f->isDir()) {
        if( $f->getExtension() === 'git') continue; // skip .git folder
        $this-> zipArchive-> addEmptyDir($f->getPathname());
        $this-> zipDir($f->getPathname());

        continue;
      }
      if ($f->isFile()) {
        if ($f->getBasename() === basename(__FILE__)) continue; // skip self 
        if ($f->getExtension() === 'zip') continue; // skip ZIP files

        $this-> zipArchive ->addFile( substr($f-> getPathname(), $this-> startPathLength) ); // remove './'

        continue;
      }

    }
  }
}
?>

Which can be used thusly:
<?php
  $host = str_replace('.', '_', $_SERVER['HTTP_HOST']);
  $date = date('Ymd-His');

  $zip = new \MakeZip("./archiv-$host-$date.zip", './', $convert_function);
  unset($zip);
?>

Add encryption or other features in the constructor.

Simple class xZip to zip big folders into multiple parts and unzip multi zip files at once.

<?php
class xZip {
    public function __construct() {}
    private function _rglobRead($source, &$array = array()) {
        if (!$source || trim($source) == "") {
            $source = ".";
        }
        foreach ((array) glob($source . "/*/") as $key => $value) {
            $this->_rglobRead(str_replace("//", "/", $value), $array);
        }
    
        foreach ((array) glob($source . "*.*") as $key => $value) {
            $array[] = str_replace("//", "/", $value);
        }
    }
    private function _zip($array, $part, $destination) {
        $zip = new ZipArchive;
        @mkdir($destination, 0777, true);
    
        if ($zip->open(str_replace("//", "/", "{$destination}/partz{$part}.zip"), ZipArchive::CREATE)) {
            foreach ((array) $array as $key => $value) {
                $zip->addFile($value, str_replace(array("../", "./"), NULL, $value));
            }
            $zip->close();
        }
    }
    public function zip($limit = 500, $source = NULL, $destination = "./") {
        if (!$destination || trim($destination) == "") {
            $destination = "./";
        }
    
        $this->_rglobRead($source, $input);
        $maxinput = count($input);
        $splitinto = (($maxinput / $limit) > round($maxinput / $limit, 0)) ? round($maxinput / $limit, 0) + 1 : round($maxinput / $limit, 0);
    
        for($i = 0; $i < $splitinto; $i ++) {
            $this->_zip(array_slice($input, ($i * $limit), $limit, true), $i, $destination);
        }
        
        unset($input);
        return;
    }
    public function unzip($source, $destination) {
        @mkdir($destination, 0777, true);
    
        foreach ((array) glob($source . "/*.zip") as $key => $value) {
            $zip = new ZipArchive;
            if ($zip->open(str_replace("//", "/", $value)) === true) {
                $zip->extractTo($destination);
                $zip->close();
            }
        }
    }
    
    public function __destruct() {}
}

//$zip = new xZip;
//$zip->zip(500, "images/", "images_zip/");
//$zip->unzip("images_zip/", "images/");
?>

A way of zipping files and downloading them thereafter:
<?php

 $files = array('image.jpeg','text.txt','music.wav');
$zipname = 'enter_any_name_for_the_zipped_file.zip';
$zip = new ZipArchive;
$zip->open($zipname, ZipArchive::CREATE);
foreach ($files as $file) {
  $zip->addFile($file);
}
$zip->close();

///Then download the zipped file.
header('Content-Type: application/zip');
header('Content-disposition: attachment; filename='.$zipname);
header('Content-Length: ' . filesize($zipname));
readfile($zipname);

?>

The following code can be used to get a list of all the file names in a zip file.

<?php
$za = new ZipArchive();

$za->open('theZip.zip');

for( $i = 0; $i < $za->numFiles; $i++ ){
    $stat = $za->statIndex( $i );
    print_r( basename( $stat['name'] ) . PHP_EOL );
}
?>

There is a usefull function to get the ZipArchive status as a human readable string :

<?php
function ZipStatusString( $status )
{
    switch( (int) $status )
    {
        case ZipArchive::ER_OK           : return 'N No error';
        case ZipArchive::ER_MULTIDISK    : return 'N Multi-disk zip archives not supported';
        case ZipArchive::ER_RENAME       : return 'S Renaming temporary file failed';
        case ZipArchive::ER_CLOSE        : return 'S Closing zip archive failed';
        case ZipArchive::ER_SEEK         : return 'S Seek error';
        case ZipArchive::ER_READ         : return 'S Read error';
        case ZipArchive::ER_WRITE        : return 'S Write error';
        case ZipArchive::ER_CRC          : return 'N CRC error';
        case ZipArchive::ER_ZIPCLOSED    : return 'N Containing zip archive was closed';
        case ZipArchive::ER_NOENT        : return 'N No such file';
        case ZipArchive::ER_EXISTS       : return 'N File already exists';
        case ZipArchive::ER_OPEN         : return 'S Can\'t open file';
        case ZipArchive::ER_TMPOPEN      : return 'S Failure to create temporary file';
        case ZipArchive::ER_ZLIB         : return 'Z Zlib error';
        case ZipArchive::ER_MEMORY       : return 'N Malloc failure';
        case ZipArchive::ER_CHANGED      : return 'N Entry has been changed';
        case ZipArchive::ER_COMPNOTSUPP  : return 'N Compression method not supported';
        case ZipArchive::ER_EOF          : return 'N Premature EOF';
        case ZipArchive::ER_INVAL        : return 'N Invalid argument';
        case ZipArchive::ER_NOZIP        : return 'N Not a zip archive';
        case ZipArchive::ER_INTERNAL     : return 'N Internal error';
        case ZipArchive::ER_INCONS       : return 'N Zip archive inconsistent';
        case ZipArchive::ER_REMOVE       : return 'S Can\'t remove file';
        case ZipArchive::ER_DELETED      : return 'N Entry has been deleted';
        
        default: return sprintf('Unknown status %s', $status );
    }
}

?>

Here is a simple function which zips folders with all sub folders or only a simple file... the $data var can be a string or an array...

<?php
public function un_zip($data,$arcpf,$mode='zip',$obj=''){
        $absoluterpfad = 'YOUR_BASE_PATH';
        $arcpf = $absoluterpfad.DS.$arcpf;
        if(is_object($obj)==false){
             $archiv = new ZipArchive();
             $archiv->open($arcpf,ZipArchive::CREATE);
        }else{$archiv =& $obj;}
        if($mode=='zip'){
           if(is_array($data)==true){
                 foreach($data as $dtmp){
                     $archiv =& un_zip($dtmp,$arcpf,'zip',&$archiv);
                 }
           }else{
            if(is_dir($data)==true){
                    $archiv->addEmptyDir(str_replace($absoluterpfad.DS,'',$data));
                  $files = scandir($data);
               $bad = array('.','..');
               $files = array_diff($files,$bad);
               foreach($files as $ftmp){
                   if(is_dir($data.DS.$ftmp)==true){
                        $archiv->addEmptyDir(str_replace($absoluterpfad.DS,'',$data.'/'.$ftmp));
                        $archiv =& un_zip($data.DS.$ftmp,$arcpf,'zip',&$archiv);
                   }elseif(is_file($data.DS.$ftmp)==true){
                    $archiv->addFile($data.DS.$ftmp,str_replace($absoluterpfad.DS,'',$data.'/'.$ftmp));
                   }
                 }
            }elseif(is_file($data)==true){$archiv->addFile($data,str_replace($absoluterpfad.DS,'',$data));}
           }
        }
        if(is_object($obj)==false){$archiv->close();}
        else{return $archiv;}
        if($mode=='unzip'){$archiv->extractTo($data);}
    }
?>

There is a limit withing PHP 5.3.3 (which seems to have been addressed in later versions; 5.3.29 seems ok on a different server).

If you try to open a zip file with more than 65,535 files in it (in my case it had 237,942 files) then you cannot access the later files. The numFiles property only reports the first 65k files.

Read a file from an archive to a variable.
A warning is printed automatically in case of a CRC32 mismatch, which we capture, so we can print our own error message.

<?php
$zip = new ZipArchive();
if ($zip->open('archive.zip')) {
  $fp = $zip->getStream('myfile.txt'); //file inside archive
  if(!$fp)
    die("Error: can't get stream to zipped file");
  $stat = $zip->statName('myfile.txt');

  $buf = ""; //file buffer
  ob_start(); //to capture CRC error message
    while (!feof($fp)) {
      $buf .= fread($fp, 2048); //reading more than 2156 bytes seems to disable internal CRC32 verification (bug?)
    }
    $s = ob_get_contents();
  ob_end_clean();
  if(stripos($s, "CRC error") != FALSE){
    echo 'CRC32 mismatch, current ';
    printf("%08X", crc32($buf)); //current CRC
    echo ', expected ';
    printf("%08X", $stat['crc']); //expected CRC
  }

  fclose($fp);
  $zip->close();
  //Done, unpacked file is stored in $buf
}
?>

To create a corrupt file, change a byte in a zip file using a hex editor.

Hi there.
I just wrote a little function to zip a whole folder while maintaining the dir-structure. I hope it might help someone.

<?php
function folderToZip($folder, &$zipFile, $subfolder = null) {
    if ($zipFile == null) {
        // no resource given, exit
        return false;
    }
    // we check if $folder has a slash at its end, if not, we append one
    $folder .= end(str_split($folder)) == "/" ? "" : "/";
    $subfolder .= end(str_split($subfolder)) == "/" ? "" : "/";
    // we start by going through all files in $folder
    $handle = opendir($folder);
    while ($f = readdir($handle)) {
        if ($f != "." && $f != "..") {
            if (is_file($folder . $f)) {
                // if we find a file, store it
                // if we have a subfolder, store it there
                if ($subfolder != null)
                    $zipFile->addFile($folder . $f, $subfolder . $f);
                else
                    $zipFile->addFile($folder . $f);
            } elseif (is_dir($folder . $f)) {
                // if we find a folder, create a folder in the zip 
                $zipFile->addEmptyDir($f);
                // and call the function again
                folderToZip($folder . $f, $zipFile, $f);
            }
        }
    }
}
?>

Use it like this:
<?php
$z = new ZipArchive();
$z->open("test.zip", ZIPARCHIVE::CREATE);
folderToZip("storeThisFolder", $z);
$z->close();
?>

Have a good day!

Important: Due to the natural file size limit of 4GB (~3,6GB to be correct) of zip files, this class will generate corrupt files of the result is larger than 4 GB. Using tar.gz is a proper alternative.

<?php
    //use bzip2 + ZipArchive to reduce file size of your zip archives.
    $zip = new ZipArchive;
    $zip->open('i.zip',ZIPARCHIVE::CREATE|ZIPARCHIVE::OVERWRITE);
    $file='wuxiancheng.cn.sql';
    $bzFilename = $file.'.bz2';
    $sql = file_get_contents($file);
    $sql = bzcompress($sql,9);
    $zip->addFromString($bzFilename,$sql);
    $zip->setArchiveComment('zipped on '.date('Y-M-d'));
?>

You can check general purpose flag to test if the zip file is encrypted. Example function below.

<?php

/**
 * Check if the file is encrypted
 * 
 * Notice: if file doesn't exists or cannot be opened, function
 * also return false.
 * 
 * @param string $pathToArchive
 * @return boolean return true if file is encrypted
 */
function isEncryptedZip( $pathToArchive ) {
    $fp = @fopen( $pathToArchive, 'r' );
    $encrypted = false;
    if ( $fp && fseek( $fp, 6 ) == 0 ) {
        $string = fread( $fp, 2 );
        if ( false !== $string ) {
            $data = unpack("vgeneral", $string);
            $encrypted = $data[ 'general' ] & 0x01 ? true : false;
        }
        fclose( $fp );
    }
    return $encrypted;
}

Be wary that there are several algorithms to generate a zip file. I found that Office OpenXML files created with ZipArchive are not recognized by Excel 2007, for example.

You have to use a different class to zip in this case, such as PclZip.