title: TinyXML Element extraction as text
body: <p>I'm trying to create an XML signature mechanism.
  my XML can be something like below:</p>
  
  <pre><code>&lt;Main&gt;
     &lt;ChildType1&gt;... &lt;/ChildType1&gt;
     &lt;ChildType2&gt;... &lt;/ChildType2&gt;
  &lt;/Main&gt;
  </code></pre>
  
  <p>In fact it would be agnostic to the kind of data below the <code>Main</code> node.
  And I only want to compute the CRC of data include into <code>Main</code> Node and after add a <code>signature</code> attribute on the <code>Main</code>.</p>
  
  <p>But for now I wrote </p>
  
  <pre><code>ostringstream ss;
  {
    boost::archive::text_oarchive oa(ss);
    ss.str("");
    try
    {
      TiXmlBase::SetCondenseWhiteSpace(false);
  
      tinyxml::Document doc;
      doc.LoadFile(filename.c_str());
  
      tinyxml::Element* schemes = tinyxml::findSingleElement&lt;SchemesSignatureException&gt;(doc, "Main");
      if (schemes == 0) throw logica_error("No Main found");
  
      tinyxml::TinyXmlFwdIterator&lt;tinyxml::Element&gt; child;
      for (child = child.begin(schemes); child != child.end(); ++child)
      {
        //the question is here, how to get the XML text of each child of the Main...
      }
  
    }
    catch (exception&amp; e)
    {
      throw ;
    }
  
  }
  string data(ss.str());
  boost::crc_32_type crc;
  crc.process_bytes(data.data(), data.size());
  </code></pre>
  
  <p>As I iterate over the child how can I get the XML text string, as for my example, first iteration will flush "... " in <code>oa</code>and second iteration "... " in <code>oa</code> ?</p>
  
  <p>I tried GetText but it always return NULL !
  Have you an idea ?</p>