The logical way to create an application to automate the building of an RSS document would be to offer the user a choice between creating an Enhanced RSS document or a Simple RSS document, and then to proceed from there.

So let's create a PHP page with a navigation bar on the left that will contain two links: 

1. Read an RSS document
   
2. Create an RSS document

The idea is to use one page on which we do everything, so we are going to create a few functions to display information according to whichever link a user has selected.

When the "Read RSS document" link is pressed, the "showfrm" function is activated; it then displays a form requesting the name of the RSS document to be opened.  Once you've entered and submitted the document name, a function called "showparsedContents" is called; it then parses the document. Below are the showfrm and showparsedContents() functions:

function showfrm(){
  echo '<form id="form1" name="form1" method="post"
action="' .$_SERVER['PHP_SELF'].'?action=parse">
  <table width="100%" border="0" cellspacing="1">
    <tr>
      <td>&nbsp;</td>
      <td width="31%">&nbsp;</td>
      <td width="48%">&nbsp;</td>
    </tr>
    <tr>
      <td width="21%" valign="top"><span class="style1">RSS
Document Location: </span></td>
      <td colspan="2" valign="top"><input name="location"
type="text" id="location" size="80" /></td>
    </tr>
    <tr>
      <td>&nbsp;</td>
      <td>&nbsp;</td>
      <td>&nbsp;</td>
    </tr>
    <tr>
      <td>&nbsp;</td>
      <td><input type="submit" name="Submit"
value="Submit" /></td>
      <td>&nbsp;</td>
    </tr>
  </table>';

  echo '</form>';
}

Here's a example of the outcome of this function:

Fig 1. A form that request RSS document name to parse...