function checkEmailArticle()
{
   var valid = true;
   if (document.frmEmailArticle.txtRecipient.value == '')
   {
      document.getElementById('valRecipient').style.display = 'inline';
      document.getElementById('valRecipientInvalid').style.display = 'none';
      valid = false;
   }
   else
   {
      document.getElementById('valRecipient').style.display = 'none';
      if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(document.frmEmailArticle.txtRecipient.value))
      {
         document.getElementById('valRecipientInvalid').style.display = 'none';
      }
      else
      {
         document.getElementById('valRecipientInvalid').style.display = 'inline';
         valid = false;
      }
   }
   if (document.frmEmailArticle.txtSender.value == '')
   {
      document.getElementById('valSender').style.display = 'inline';
      document.getElementById('valSenderInvalid').style.display = 'none';
      valid = false;
   }
   else
   {
      document.getElementById('valSender').style.display = 'none';
      if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(document.frmEmailArticle.txtSender.value))
      {
         document.getElementById('valSenderInvalid').style.display = 'none';
      }
      else
      {
         document.getElementById('valSenderInvalid').style.display = 'inline';
         valid = false;
      }
   }
   if (document.frmEmailArticle.txtSubject.value == '')
   {
      document.getElementById('valSubject').style.display = 'inline';
      valid = false;
   }
   else
   {
      document.getElementById('valSubject').style.display = 'none';
   }
   return valid;
}

function emailArticle(query_string)
{
   var parameters = 'txtRecipient=' + document.frmEmailArticle.txtRecipient.value;
   parameters += '&txtSender=' + document.frmEmailArticle.txtSender.value;
   parameters += '&txtSubject=' + document.frmEmailArticle.txtSubject.value;
   parameters += '&txtMessage=' + document.frmEmailArticle.txtMessage.value;
   var request = new AjaxRequest();
   request.onreadystatechange = function()
   {
      if ((request.readyState == 4) && (request.status == 200))
      {
      }
   }
   request.open('POST', siteRoot + 'ajax/email_article.php?' + query_string, true);
   request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
   request.setRequestHeader("Content-length", parameters.length);
   request.setRequestHeader("Connection", "close");
   request.setRequestHeader('If-Modified-Since', 'Sat, 1 Jan 2000 00:00:00 GMT');
   request.send(parameters);
}