stream_filter_register

Register a stream filter implemented as a PHP class derived from php_user_filter (PHP 5)
bool stream_filter_register ( string filtername, string classname )

int filter ( resource in, resource out, int &consumed, bool closing )

bool onCreate ( )

void onClose ( )

Example 2375. Filter for capitalizing characters on foo-bar.txt stream

<?php

/* Define our filter class */
class strtoupper_filter extends php_user_filter {

  function filter($in, $out, &$consumed, $closing) 

  {

    while ($bucket = stream_bucket_make_writeable($in)) {

      $bucket->data = strtoupper($bucket->data);

      $consumed += $bucket->datalen;

      stream_bucket_append($out, $bucket);

    }

    return PSFS_PASS_ON;

  }

} 

/* Register our filter with PHP */
stream_filter_register("strtoupper", "strtoupper_filter")

    or die("Failed to register filter");

$fp = fopen("foo-bar.txt", "w");

/* Attach the registered filter to the stream just opened */
stream_filter_append($fp, "strtoupper");

fwrite($fp, "Line1\n");
fwrite($fp, "Word - 2\n");
fwrite($fp, "Easy As 123\n");

fclose($fp);

/* Read the contents back out

 */
readfile("foo-bar.txt");

?>

The above example will output:

copy to clipboard

LINE1

WORD - 2

EASY AS 123

Example 2376. Registering a generic filter class to match multiple filter names.

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<?php

/* Define our filter class */
class string_filter extends php_user_filter {

  var $mode;


  function filter($in, $out, &$consumed, $closing) 

  {

    while ($bucket = stream_bucket_make_writeable($in)) {

      if ($this->mode == 1) {

        $bucket->data = strtoupper($bucket->data);

      } elseif ($this->mode == 0) {

        $bucket->data = strtolower($bucket->data);

      }


      $consumed += $bucket->datalen;

      stream_bucket_append($out, $bucket);

    }

    return PSFS_PASS_ON;

  }


  function onCreate() 

  {

    if ($this->filtername == 'str.toupper') {

      $this->mode = 1;

    } elseif ($this->filtername == 'str.tolower') {

      $this->mode = 0;

    } else {

      /* Some other str.* filter was asked for,

         report failure so that PHP will keep looking */

      return false;

    }


    return true;

  }

} 

/* Register our filter with PHP */
stream_filter_register("str.*", "string_filter")

    or die("Failed to register filter");

$fp = fopen("foo-bar.txt", "w");

/* Attach the registered filter to the stream just opened 

   We could alternately bind to str.tolower here */
stream_filter_append($fp, "str.toupper");

fwrite($fp, "Line1\n");
fwrite($fp, "Word - 2\n");
fwrite($fp, "Easy As 123\n");

fclose($fp);

/* Read the contents back out

 */
readfile("foo-bar.txt");
?>

The above example will output:

copy to clipboard

LINE1

WORD - 2

EASY AS 123

stream_filter_register

Register a stream filter implemented as a PHP class derived from php_user_filter (PHP 5) bool stream_filter_register ( string filtername, string classname ) int filter ( resource in, resource out, int &consumed, bool closing ) bool onCreate ( ) void onClose ( )

Example 2375. Filter for capitalizing characters on foo-bar.txt stream

Example 2376. Registering a generic filter class to match multiple filter names.

Change Language

Register a stream filter implemented as a PHP class derived from php_user_filter (PHP 5)
bool stream_filter_register ( string filtername, string classname )

int filter ( resource in, resource out, int &consumed, bool closing )

bool onCreate ( )

void onClose ( )