stream_filter_register

PHP 5, PHP 7, PHP 8

stream_filter_register - Register a user defined stream filter

Manual

Code Examples

Example #1 Filter for capitalizing characters on <span class='function-filename'>foo-bar.txt</span> stream

Result: LINE1 WORD - 2 EASY AS 123

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Example #2 Registering a generic filter class to match multiple filter names.

Result: LINE1 WORD - 2 EASY AS 123

<?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");

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PHP Version:

stream_filter_register

Example #1 Filter for capitalizing characters on <span class='function-filename'>foo-bar.txt</span> stream

Example #2 Registering a generic filter class to match multiple filter names.

Function stream_filter_register:

Streams Functions

Most used PHP functions