title: Get all valid attributes for a given XML element
body: <p>I Loaded an XML document inside an <code>XmlDocument</code>. The document is loaded by an <code>XmlReader</code> that is binded to a given schema (by the <code>XmlReaderSettings</code> class).</p>
  
  <p>How can I get a list of allowed attributes for a given document node element?</p>
  
  <p>XML looks like this and has optional attributes:</p>
  
  <pre><code>&lt;row attribute1="1" attribute2="2" attribute3="something"&gt;
  &lt;row attribute1="3" attribute3="something"&gt;
  &lt;row attribute2="1" attribute3="something"&gt;
  </code></pre>
  
  <p>The list should contain attribute1, attribute2, attribute3</p>
  
  <p>Thanks</p>