完整的 XHTML 和 JavaScript 示例

以下是使用 XHTML 和 PHP 作为单个文件提供的完整示例。

<?php
if (isset($_SERVER['HTTP_ACCEPT']) && stristr($_SERVER['HTTP_ACCEPT'],'application/xhtml+xml'))
{
 // Client header isset` and explicitly declares XHTML parser support.
 header('Content-Type: application/xhtml+xml; charset=UTF-8');
 echo '<?xml version="1.0" encoding="UTF-8"?>'."\n";
 echo '<!DOCTYPE html>'."\n";
 echo '<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">'."\n";
}
else
{
 //Some browsers do not declare support, IE9 shamelessly uses `*/*` in example.
 echo '<!DOCTYPE html>'."\n";
 echo '<html>'."\n";
}
?>
<head>
<style type="text/css">
* {border: 0; margin: 0; padding: 0;}
</style>
<script type="application/javascript">
//<![CDATA[
window.onload = function(event)
{
 alert('This JavaScript alert will load once the page has loaded.');
}
//]]>
</script>
</head>

<body>

<h1><span>XHTML and JavaScript Simple Demonstration</span></h1>

</body>
</html>