XForms defines a variation on traditional
webforms which allows them to be used on a wider variety of platforms and
browsers or even non-traditional media such as PDF documents.
The first key difference in XForms is how the form is sent to the client.
XForms for HTML Authors
contains a detailed description of how to create XForms, for the purpose
of this tutorial we'll only be looking at a simple example.
The above form displays a text input box (named q),
and a submit button. When the submit button is clicked, the form will be
sent to the page referred to by action.
Here's where it starts to look different from your web application's point
of view. In a normal HTML form, the data would be sent as
application/x-www-form-urlencoded, in the XForms world
however, this information is sent as XML formatted data.
If you're choosing to work with XForms then you probably want that data as
XML, in that case, look in $HTTP_RAW_POST_DATA where
you'll find the XML document generated by the browser which you can pass
into your favorite XSLT engine or document parser.
If you're not interested in formatting and just want your data to be loaded
into the traditional $_POST variable, you can instruct
the client browser to send it as application/x-www-form-urlencoded
by changing the method attribute to