Like the string.* filters, the convert.* filters perform actions similar to their names. For more information on a given filter, refer to the manual page for the corresponding function.
Use of these filters are equivalent to processing all stream data through the base64_encode() and base64_decode() functions respectively. convert.base64-encode
supports parameters given as an associative array. If line-length
is given, the base64 output will be split into chunks of line-length
characters each. If line-break-chars
is given, each chunk will be delimited by the characters given. These parameters give the same effect as using base64_encode() with chunk_split().
Example #1 convert.base64-encode & convert.base64-decode
<?php
$fp = fopen('php://output', 'w');
stream_filter_append($fp, 'convert.base64-encode');
fwrite($fp, "This is a test.\n");
fclose($fp);
$param = array('line-length' => 8, 'line-break-chars' => "\r\n");
$fp = fopen('php://output', 'w');
stream_filter_append($fp, 'convert.base64-encode', STREAM_FILTER_WRITE, $param);
fwrite($fp, "This is a test.\n");
fclose($fp);
$fp = fopen('php://output', 'w');
stream_filter_append($fp, 'convert.base64-decode');
fwrite($fp, "VGhpcyBpcyBhIHRlc3QuCg==");
fclose($fp);
?>
Use of the decode version of this filter is equivalent to processing all stream data through the quoted_printable_decode() function. There is no function equivalent to convert.quoted-printable-encode
. convert.quoted-printable-encode
supports parameters given as an associative array. In addition to the parameters supported by convert.base64-encode
, convert.quoted-printable-encode
also supports boolean arguments binary
and force-encode-first
. convert.base64-decode
only supports the line-break-chars
parameter as a type-hint for stripping from the encoded payload.
Example #2 convert.quoted-printable-encode & convert.quoted-printable-decode
<?php
$fp = fopen('php://output', 'w');
stream_filter_append($fp, 'convert.quoted-printable-encode');
fwrite($fp, "This is a test.\n");
?>
The convert.iconv.*
filters are available, if iconv support is enabled, and their use is equivalent to processing all stream data with iconv(). These filters do not support parameters, but instead expect the input and output encodings to be given as part of the filter name, i.e. either as convert.iconv.<input-encoding>.<output-encoding>
or convert.iconv.<input-encoding>/<output-encoding>
(both notations are semantically equivalent).
Example #3 convert.iconv.*
<?php
$fp = fopen('php://output', 'w');
stream_filter_append($fp, 'convert.iconv.utf-16le.utf-8');
fwrite($fp, "T\0h\0i\0s\0 \0i\0s\0 \0a\0 \0t\0e\0s\0t\0.\0\n\0");
fclose($fp);
?>