<?xml version="1.0" encoding="iso-8859-1"?>
<!-- $Revision: 1.7 $ -->
<!-- splitted from ./en/functions/classobj.xml, last change in rev 1.33 -->
 <refentry id="function.is-a">
   <refnamediv>
    <refname>is_a</refname>
    <refpurpose>
     Returns &true; if the object is of this class or has this class as 
     one of its parents
    </refpurpose>
   </refnamediv>
   <refsect1>
    <title>Description</title>
     <methodsynopsis>
      <type>bool</type><methodname>is_a</methodname>
      <methodparam><type>object</type><parameter>object</parameter></methodparam>
      <methodparam><type>string</type><parameter>class_name</parameter></methodparam>
     </methodsynopsis>
    <para>
     This function returns &true; if the object is of this class or 
     has this class as one of its parents, &false; otherwise.
    </para>
    <para>
      <example>
        <title><function>is_a</function> example</title>
        <programlisting role="php">
<![CDATA[
<?php
// define a class
class WidgetFactory
{
  var $oink = 'moo';
}

// create a new object
$WF = new WidgetFactory();

if (is_a($WF, 'WidgetFactory')) {
  echo "yes, \$WF is still a WidgetFactory\n";
}
?>
]]>
        </programlisting>
      </example>
    </para>
    <para>
     The <function>is_a</function> function is deprecated as of PHP 5 in
     favor of the <link linkend="language.operators.type">instanceof</link>
     type operator.  In the above example we could use the following in
     PHP 5:
    </para>
    <para>
     <example>
      <title>Using the <emphasis>instanceof</emphasis> operator in PHP 5</title>
      <programlisting role="php">
<![CDATA[
<?php
if ($WF instanceof WidgetFactory) {
    echo 'Yes, $WF is a WidgetFactory';
}
?>
]]>
      </programlisting>
     </example>
    </para>
    <simpara>
     See also <function>get_class</function>, 
     <function>get_parent_class</function>, and 
     <function>is_subclass_of</function>.
    </simpara>
   </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:"../../../../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
-->