预定义常量

下列常量由此扩展定义，且仅在此扩展编译入 PHP 或在运行时动态载入时可用。

FORCE_GZIP (int)
FORCE_DEFLATE (int)
ZLIB_ENCODING_RAW (int): DEFLATE algorithm as per RFC 1951. Available as of PHP 7.0.0.
ZLIB_ENCODING_DEFLATE (int): ZLIB compression algorithm as per RFC 1950. Available as of PHP 7.0.0.
ZLIB_ENCODING_GZIP (int): GZIP algorithm as per RFC 1952. Available as of PHP 7.0.0.
ZLIB_FILTERED (int): Available as of PHP 7.0.0.
ZLIB_HUFFMAN_ONLY (int): Available as of PHP 7.0.0.
ZLIB_FIXED (int): Available as of PHP 7.0.0.
ZLIB_RLE (int): Available as of PHP 7.0.0.
ZLIB_DEFAULT_STRATEGY (int): Available as of PHP 7.0.0.
ZLIB_BLOCK (int): Available as of PHP 7.0.0.
ZLIB_NO_FLUSH (int): Available as of PHP 7.0.0.
ZLIB_PARTIAL_FLUSH (int): Available as of PHP 7.0.0.
ZLIB_SYNC_FLUSH (int): Available as of PHP 7.0.0.
ZLIB_FULL_FLUSH (int): Available as of PHP 7.0.0.
ZLIB_FINISH (int): Available as of PHP 7.0.0.

Php/docs/zlib.constants