将发布的数据插入XML

I am looking to insert data from a PHP form in to an XML document and print it in the browser. Can someone point me in the right direction?

Something similar to:

Form:

<form name="createDoc" action="createDocument.php" method="post">
  <input name="name" type="text" id="name"> 
</form>

XML:

<?xml version="1.0" encoding="UTF-8"?>
<doc>
    <article id="0001">
        <title>My book</title>
    <para>Lorem ipsum dolor sit amet, **[name here]** consectetur adipiscing elit. Phasellus consequat purus ac tellus imperdiet ullamcorper.</para>
    </article>
</doc>

Result:

Lorem ipsum dolor sit amet, Joh Doe consectetur adipiscing elit. Phasellus consequat purus ac tellus imperdiet ullamcorper.

Thanks in advance :)

The fastest way is to put the XML into a string, and use

str_replace("**[name here]**",$_POST[name],$xmlstr);

In the future, you may want to post what you've already tried. We are here to help you figure out a problem, not solve it for you.