(PHP 5 >= 5.4.0, PHP 7)
zlib_encode — Compress data with the specified encoding
$data
, string $encoding
[, string $level = -1
] )Compress data with the specified encoding.
This function is currently not documented; only its argument list is available.
data
encoding
level
RFC 1950 - zlib
RFC 1951 - raw deflate
RFC 1952 - gzip
The $encoding parameter referers to the window bits. So you can encode in several formats:
<?php
// RFC 1950 - zlib
$compressedData = zlib_encode($uncompressedData, 15);
// RFC 1951 - raw deflate
$compressedData = zlib_encode($uncompressedData, -15);
// RFC 1952 - gzip
$compressedData = zlib_encode($uncompressedData, 31);
?>
Undocumented constants are:
ZLIB_ENCODING_RAW
ZLIB_ENCODING_GZIP
ZLIB_ENCODING_DEFLATE
Example code:
<?php
$in='hello world';
$enc=zlib_encode($in, ZLIB_ENCODING_DEFLATE);
echo zlib_decode($enc);
//outputs 'hello world'
?>
