deflate_add

(PHP 7)

deflate_addIncrementally deflate data

说明

deflate_add ( resource $context , string $data [, int $flush_mode = ZLIB_SYNC_FLUSH ] ) : string

Incrementally deflates data in the specified context.

参数

context

A context created with deflate_init().

data

A chunk of data to compress.

flush_mode

One of ZLIB_BLOCK, ZLIB_NO_FLUSH, ZLIB_PARTIAL_FLUSH, ZLIB_SYNC_FLUSH (default), ZLIB_FULL_FLUSH, ZLIB_FINISH. Normally you will want to set ZLIB_NO_FLUSH to maximize compression, and ZLIB_FINISH to terminate with the last chunk of data. See the » zlib manual for a detailed description of these constants.

返回值

Returns a chunk of compressed data, 或者在失败时返回 FALSE.

错误/异常

If invalid arguments are given, an error of level E_WARNING is generated.

参见

User Contributed Notes

douglasjam at gmail dot com 12-Jul-2018 10:03
Example about to use deflate functions to write a gzip encoded file in chunks.

<?php

$handler
= fopen('/tmp/test.csv', 'w');
$deflateContext = deflate_init(ZLIB_ENCODING_GZIP, ['level' => 9]);

$strings = [
   
'Hello, how are you?' . PHP_EOL,
   
'I am fine thanks' . PHP_EOL,
   
'Hello, how are you?' . PHP_EOL,
];

foreach (
$strings as $string) {
   
fwrite($handler, deflate_add($deflateContext, $string, ZLIB_NO_FLUSH));
}

fwrite($handler, deflate_add($deflateContext, '', ZLIB_FINISH));
fclose($handler);

echo
gzdecode(file_get_contents('/tmp/test.csv'));