Difficulties to output "HTML-string code" through XML

I got som difficulties to output "HTML-string code" through XML.I have presented a example below. In the server-side I have some code written in PHP.

$htmlCode = "<div>...........................</div>";

header("Content-type: text/xml");

echo "<?xml version='1.0' encoding='ISO-8859-1'?>";
echo "<info>";
echo "<htmlCode>";
echo $htmlCode;
echo "</htmlCode>";
echo "</info>";

The problem lies in that "HTML string code" or $htmlCode above has tag elements, so the "HTML string codes" will be treated as XML code. And I want the output to be treated as a string.

And in the clientside I have a "AJAX call" to retrieve the string of HTML code.

document.getElementById('someID').innerH开发者_高级运维TML=xmlhttp.responseXML.getElementsByTagName("htmlCode")[0].childNodes[0].nodeValue;//I got nothing because the string is treated as XML code.

How do I solve this problem? I hope I have been specific enough for you to understand my problem.

You are looking for CDATA.

The term CDATA is used about text data that should not be parsed by the XML parser.

Everything inside a CDATA section is ignored by the parser.

A CDATA section starts with <![CDATA[ and ends with ]]>:

// escape closing tags
$htmlCode = str_replace("]]>", "<![CDATA[]]]]><![CDATA[>]]>", $htmlCode);

echo "<?xml version='1.0' encoding='ISO-8859-1'?>";
echo "<info>";
echo "<htmlCode>";
echo "<![CDATA[".$htmlCode."]]>";
echo "</htmlCode>";
echo "</info>";

Added escaping fix from here

Don't build XML from strings. Just don't. There are ready-to-use libraries that do the right thing. PHP's DOM implementation is one of them.

$myHtmlString = "<div>Some HTML</div>";

$xml  = new DOMDocument('1.0', 'utf-8');

$info = $xml->createElement('info');
$xml->appendChild($info);

$htmlCode = $xml->createElement('htmlCode', $myHtmlString);
$info->appendChild($htmlCode);

echo $xml->saveXML();

This seems like the more complicated approach, but in fact this makes sure your XML is correct. In contrast, just throwing a few strings together will go wrong at some point.

Use htmlspecialchars(). Although this function is named after HTML, it is also quite acceptable for XML. (htmlentities() wouldn't be, but you almost never want to use that one anyway.)

<?php
    $htmlCode = "<div>...........................</div>";

    header("Content-type: text/xml");
    echo '<?xml encoding="ISO-8859-1"?>'; // really? sure?
?>
<info>
    <htmlCode><?php echo htmlspecialchars($htmlCode); ?></htmlCode>
</info>

Using a CDATASection is also OK, but given that you need to escape the sequence ]]> in that case, there's really not much advantage over XML-encoding.