Examples

This example opens a temporary file and writes a test string to it, then it prints out the content of this file twice.

Example #1 Small Zlib Example


<?php

$filename = tempnam('/tmp', 'zlibtest') . '.gz';
echo "<html>\n<head></head>\n<body>\n<pre>\n";
$s = "Only a test, test, test, test, test, test, test, test!\n";

// open file for writing with maximum compression
$zp = gzopen($filename, "w9");

// write string to file
gzwrite($zp, $s);

// close file
gzclose($zp);

// open file for reading
$zp = gzopen($filename, "r");

// read 3 char
echo gzread($zp, 3);

// output until end of the file and close it.
gzpassthru($zp);
gzclose($zp);

echo "\n";

// open file and print content (the 2nd time).
if (readgzfile($filename) != strlen($s)) {
        echo "Error with zlib functions!";
}
unlink($filename);
echo "</pre>\n</body>\n</html>\n";

?>

Example #2 Working with the incremental compression and decompression API as of PHP 7.0.0


// Perform GZIP compression:
$deflateContext = deflate_init(ZLIB_ENCODING_GZIP);
$compressed = deflate_add($deflateContext, "Data to compress", ZLIB_NO_FLUSH);
$compressed .= deflate_add($deflateContext, ", more data", ZLIB_NO_FLUSH);
$compressed .= deflate_add($deflateContext, ", and even more data!", ZLIB_FINISH);?>

// Perform GZIP decompression:
$inflateContext = inflate_init(ZLIB_ENCODING_GZIP);
$uncompressed = inflate_add($inflateContext, $compressed, ZLIB_NO_FLUSH);
$uncompressed .= inflate_add($inflateContext, NULL, ZLIB_FINISH);
echo $uncompressed;

The above example will output:

Data to compress, more data, and even more data!