预定义常量

Since PHP 4.3.0 it is possible to identify at runtime which iconv implementation is adopted by this extension.

*iconv* constants
Name	Type	Description
ICONV_IMPL	string	The implementation name
ICONV_VERSION	string	The implementation version

Note: Writing implementation-dependent scripts with these constants is strongly discouraged.

Since PHP 5.0.0, the following constants are also available:

*iconv* constants available since PHP 5.0.0
Name	Type	Description
ICONV_MIME_DECODE_STRICT	integer	A bitmask used for iconv_mime_decode()
ICONV_MIME_DECODE_CONTINUE_ON_ERROR	integer	A bitmask used for iconv_mime_decode()