function GetXmlHttpObject(handler)
{
   var objXMLHttp=null
   if (window.XMLHttpRequest)
   {
       objXMLHttp=new XMLHttpRequest()
   }
   else if (window.ActiveXObject)
   {
       objXMLHttp=new ActiveXObject("Microsoft.XMLHTTP")
   }
   return objXMLHttp
}

function stateChanged()
{
   
   document.getElementById("txtResult").innerHTML = '<Div float="center" align="center"><IMG alt="Loading" height="200" src="images/ajax-loader.gif" width="100"></Div>';
      if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
   {        
           document.getElementById("txtResult").innerHTML=xmlHttp.responseText
   }
   else {
           //alert(xmlHttp.status);
   }
}

function htmlData(url, qStr)
{
   if (url.length==0)
   {
       document.getElementById("txtResult").innerHTML='';
       return;
   }
   xmlHttp=GetXmlHttpObject()
   if (xmlHttp==null)
   {
       alert ("Browser does not support HTTP Request");
       return;
   }

   url=url+"?"+qStr;
   url=url+"&sid="+Math.random();
   xmlHttp.onreadystatechange=stateChanged;
   xmlHttp.open("GET",url,true) ;
   xmlHttp.send(null);
}
function SendMail(messageId)
{
   var message =  document.getElementById('message').value;
   var subject =  document.getElementById('subject').value;
   var studentId =  document.getElementById('studentId').value;
   queryString = 'MID='+ messageId + '&nMode=3&message='+ message + '&subject='+ subject+ '&SID='+ studentId;
   htmlData('message.php',queryString);   
}

function PostAnnouncement(messageId)
{
   var announcement =  document.getElementById('announcement').value;
   var startdate =  document.getElementById('txtStartDate').value;
   var enddate =  document.getElementById('txtEndDate').value;
   queryString = 'MID='+ messageId + '&nMode=2&Announcement='+ announcement + '&Startdate='+ startdate+ '&Enddate='+ enddate;
   htmlData('announcements.php',queryString);   
}