title: exception has been thrown by the target of an invocation c#
body: <p>I am trying to concat two string from a datatable and display it in a rich text box.</p>
  
  <p>I get "exception has been thrown by the target of an invocation" error when executing below code. Kindly help. </p>
  
  <pre><code>Rchtxt_Editor1.Document 
  = ImportHtml(string.Concat("&lt;P&gt;string1&lt;/P&gt;","&lt;P&gt;string2&lt;/P&gt;"));
  
  
         public RadDocument ImportHtml(string content)
          {
   XamlFormatProvider provider = new XamlFormatProvider();
              return provider.Import(content);
      }
  </code></pre>