stream_filter_register

bool **stream_filter_register** string $filter_name string $class

allows you to implement

your own filter on any registered stream used with all the other filesystem functions (such as , etc.). stream_filter_register``fopen``fread

filter_nameThe filter name to be registered.

class To implement a filter, you need to define a class as an extension of with a number of member functions. When performing read/write operations on the stream to which your filter is attached, PHP will pass the data through your filter (and any other filters attached to that stream) so that the data may be modified as desired. You must implement the methods exactly as described in - doing otherwise will lead to undefined behaviour. php_user_filter``php_user_filter

return.success

will return false if the
is already defined.

stream_filter_register``filter_name

Voorbeeld: Filter for capitalizing characters on stream

 The example below implements a filter named 
 on the  stream which will capitalize
 all letter characters written to/read from that stream.
`strtoupper`

<?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");

?>

LINE1
WORD - 2
EASY AS 123

Voorbeeld: Registering a generic filter class to match multiple filter names.

<?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");
?>

LINE1
WORD - 2
EASY AS 123

stream_wrapper_register``stream_filter_append``stream_filter_prepend

Vorige ← stream_filter_prepend Volgende stream_filter_remove →

stream_filter_register

stream_filter_register

Documentatie