php-doc-en/reference/filter/book.xml
Christoph Michael Becker dff279a1fb Fix #76259: Sessions extension does not strictly match Core extention definition
We update the extension-membership of the respective extensions,
and fix the installation instructions where necessary.

git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@344870 c90b9560-bf6c-de11-be94-00142212c4b1
2018-04-27 16:42:29 +00:00

70 lines
2.3 KiB
XML

<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<book xml:id="book.filter" xmlns="http://docbook.org/ns/docbook">
<?phpdoc extension-membership="bundled" ?>
<title>Data Filtering</title>
<titleabbrev>Filter</titleabbrev>
<preface xml:id="intro.filter">
&reftitle.intro;
<para>
This extension filters data by either validating or sanitizing it. This is
especially useful when the data source contains unknown (or foreign) data,
like user supplied input. For example, this data may come from an HTML form.
</para>
<para>
There are two main types of filtering:
<emphasis>validation</emphasis> and <emphasis>sanitization</emphasis>.
</para>
<para>
<link linkend="filter.filters.validate">Validation</link> is used to
validate or check if the data meets certain qualifications. For example,
passing in <constant>FILTER_VALIDATE_EMAIL</constant> will determine if
the data is a valid email address, but will not change the data itself.
</para>
<para>
<link linkend="filter.filters.sanitize">Sanitization</link> will
sanitize the data, so it may alter it by removing undesired characters.
For example, passing in <constant>FILTER_SANITIZE_EMAIL</constant> will
remove characters that are inappropriate for an email address to contain.
That said, it does not validate the data.
</para>
<para>
<emphasis>Flags</emphasis> are optionally used with both validation and
sanitization to tweak behaviour according to need. For example, passing
in <constant>FILTER_FLAG_PATH_REQUIRED</constant> while filtering an
<acronym>URL</acronym> will require a path (like <literal>/foo</literal>
in <literal>http://example.org/foo</literal>) to be present.
</para>
</preface>
&reference.filter.setup;
&reference.filter.filters;
&reference.filter.constants;
&reference.filter.examples;
&reference.filter.reference;
</book>
<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"~/.phpdoc/manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->