php-doc-en/reference/strings/functions/addcslashes.xml
Adam Harvey ab480f7d49 Clarify the charlist warning on the addcslashes() page.
Fixes doc bug #65789 (addcslashes "predefined escape sequences").


git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@331629 c90b9560-bf6c-de11-be94-00142212c4b1
2013-10-01 17:22:13 +00:00

175 lines
4.8 KiB
XML

<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<refentry xmlns="http://docbook.org/ns/docbook" xml:id="function.addcslashes">
<refnamediv>
<refname>addcslashes</refname>
<refpurpose>Quote string with slashes in a C style</refpurpose>
</refnamediv>
<refsect1 role="description">
&reftitle.description;
<methodsynopsis>
<type>string</type><methodname>addcslashes</methodname>
<methodparam><type>string</type><parameter>str</parameter></methodparam>
<methodparam><type>string</type><parameter>charlist</parameter></methodparam>
</methodsynopsis>
<para>
Returns a string with backslashes before characters that are
listed in <parameter>charlist</parameter> parameter.
</para>
</refsect1>
<refsect1 role="parameters">
&reftitle.parameters;
<para>
<variablelist>
<varlistentry>
<term><parameter>str</parameter></term>
<listitem>
<para>
The string to be escaped.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>charlist</parameter></term>
<listitem>
<para>
A list of characters to be escaped. If
<parameter>charlist</parameter> contains characters
<literal>\n</literal>, <literal>\r</literal> etc., they are
converted in C-like style, while other non-alphanumeric characters
with ASCII codes lower than 32 and higher than 126 converted to
octal representation.
</para>
<para>
When you define a sequence of characters in the charlist argument
make sure that you know what characters come between the
characters that you set as the start and end of the range.
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
echo addcslashes('foo[ ]', 'A..z');
// output: \f\o\o\[ \]
// All upper and lower-case letters will be escaped
// ... but so will the [\]^_`
?>
]]>
</programlisting>
</informalexample>
Also, if the first character in a range has a higher ASCII value
than the second character in the range, no range will be
constructed. Only the start, end and period characters will be
escaped. Use the <function>ord</function> function to find the
ASCII value for a character.
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
echo addcslashes("zoo['.']", 'z..A');
// output: \zoo['\.']
?>
]]>
</programlisting>
</informalexample>
</para>
<para>
Be careful if you choose to escape characters 0, a, b, f, n, r, t and
v. They will be converted to \0, \a, \b, \f, \n, \r, \t and \v, all of
which are predefined escape sequences in C. Many of these sequences are
also defined in other C-derived languages, including PHP, meaning that
you may not get the desired result if you use the output of
<function>addcslashes</function> to generate code in those languages
with these characters defined in <parameter>charlist</parameter>.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1 role="returnvalues">
&reftitle.returnvalues;
<para>
Returns the escaped string.
</para>
</refsect1>
<refsect1 role="changelog">
&reftitle.changelog;
<para>
<informaltable>
<tgroup cols="2">
<thead>
<row>
<entry>&Version;</entry>
<entry>&Description;</entry>
</row>
</thead>
<tbody>
<row>
<entry>5.2.5</entry>
<entry>
The escape sequences \v and \f were added.
</entry>
</row>
</tbody>
</tgroup>
</informaltable>
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<para>
<parameter>charlist</parameter> like "\0..\37", which would
escape all characters with ASCII code between 0 and 31.
<example>
<title><function>addcslashes</function> example</title>
<programlisting role="php">
<![CDATA[
<?php
$escaped = addcslashes($not_escaped, "\0..\37!@\177..\377");
?>
]]>
</programlisting>
</example>
</para>
</refsect1>
<refsect1 role="seealso">
&reftitle.seealso;
<para>
<simplelist>
<member><function>stripcslashes</function></member>
<member><function>stripslashes</function></member>
<member><function>addslashes</function></member>
<member><function>htmlspecialchars</function></member>
<member><function>quotemeta</function></member>
</simplelist>
</para>
</refsect1>
</refentry>
<!-- 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
-->