- Updated the first example with PEAR CS

- Added a line to the intro stating the method works fine with objects
- Added second example with information about the differences between isset


git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@165216 c90b9560-bf6c-de11-be94-00142212c4b1

reference/array/functions/array-key-exists.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.8 $ -->
+<!-- $Revision: 1.9 $ -->
 <!-- splitted from ./en/functions/array.xml, last change in rev 1.119 -->
   <refentry id="function.array-key-exists">
    <refnamediv>
@@ -17,7 +17,11 @@
      <function>array_key_exists</function> returns &true; if the
      given <parameter>key</parameter> is set in the array.
      <parameter>key</parameter> can be any value possible
-     for an array index.
+     for an array index. <function>array_key_exists</function> also works
+     on objects.
+    </para>
+    <para>
+     
     </para>
     <para>
      <example>
@@ -25,8 +29,8 @@
       <programlisting role="php">
 <![CDATA[
 <?php
-$search_array = array("first" => 1, "second" => 4);
-if (array_key_exists("first", $search_array)) {
+$search_array = array('first' => 1, 'second' => 4);
+if (array_key_exists('first', $search_array)) {
     echo "The 'first' element is in the array";
 }
 ?>
@@ -40,6 +44,27 @@ if (array_key_exists("first", $search_array)) {
       in PHP 4.0.6.
      </simpara>
     </note>
+    <example>
+     <title><function>array_key_exists</function> vs <function>isset</function></title>
+     <para>
+      <function>isset</function> does not return &true; for array keys
+      that correspond to a &null; value, while
+      <function>array_key_exists</function> does.
+     </para>
+      <programlisting role="php">
+<![CDATA[
+<?php
+$search_array = array('first' => null, 'second' => 4);
+
+// returns false
+isset($search_array['first'])
+
+// returns true
+array_key_exists('first', $search_array);
+?>
+]]>
+      </programlisting>
+    </example>
     <para>
      See also <function>isset</function>, 
      <function>array_keys</function>, and