title: How to ignore the validation of Unknown tags?
body: <p>One more challenge to the XSD capability,<br><br>I have been sending XML files by my clients, which will be having 0 or more undefined or [call] unexpected tags (May appear in hierarchy). Well they are redundant tags for me .. so I have got to ignore their presence,  but along with them there are some set of tags which are required to be validated.</p>
  
  <p>This is a sample XML:</p>
  
  <pre><code>&lt;root&gt;
    &lt;undefined_1&gt;one&lt;/undefined_1&gt;
    &lt;undefined_2&gt;two&lt;/undefined_2&gt;
    &lt;node&gt;to_be_validated&lt;/node&gt;
    &lt;undefined_3&gt;two&lt;/undefined_3&gt;
    &lt;undefined_4&gt;two&lt;/undefined_4&gt;
  &lt;/root&gt;
  </code></pre>
  
  <p>And the XSD I tried with:</p>
  
  <pre><code>  &lt;xs:element name="root" type="root"&gt;&lt;/xs:element&gt;
    &lt;xs:complexType name="root"&gt;
      &lt;xs:sequence&gt;
        &lt;xs:any maxOccurs="2" minOccurs="0"/&gt;
        &lt;xs:element name="node" type="xs:string"/&gt;
        &lt;xs:any maxOccurs="2" minOccurs="0"/&gt;
      &lt;/xs:sequence&gt;
    &lt;/xs:complexType
  </code></pre>
  
  <p>XSD doesn't allow this, due to certain reasons.<br>
  The above mentioned example is just a sample. The practical XML comes with the complex hierarchy of XML tags ..</p>
  
  <p>Kindly let me know if you can get a hack of it.</p>
  
  <p>By the way, The alternative solution is to insert XSL-transformation, before validation process. Well, I am avoiding it because I need to change the .Net code which triggers validation process, which is supported at the least by my company.</p>