var req = null;
function processReqChange() {
  if (req.readyState == 4 && req.status == 200 ) {
    var dobj = document.getElementById( 'dynamicPart' );
    dobj.innerHTML = req.responseText;
  }
}

function loadUrl( tab ) {
  var url = window.location.toString();
  //url = url.replace( /index.html/, tab );
  url = url + tab + "?hello=" + Math.random(); // the random number prevents IE from caching it forever
  if(window.XMLHttpRequest) {
    try { req = new XMLHttpRequest();
    } catch(e) { req = false; }
  } else if(window.ActiveXObject) {
    try { req = new ActiveXObject('Msxml2.XMLHTTP');
    } catch(e) {
    try { req = new ActiveXObject('Microsoft.XMLHTTP');
    } catch(e) { req = false; }
  } }
  if(req) {
    req.onreadystatechange = processReqChange;
    req.open('GET', url, true);
    req.send('');
  }
}
var pageOne = "MCA";
//var pageTwo = "ME12H";
var pageThree = "MR12";

var selectPOne = '<span class="CourseLinkSelected"><a href="javascript: void pOne();">' + pageOne + '</a></span>';
var unselectPOne = '<span class="CourseLink"> <a href="javascript: void pOne();" >' + pageOne + '</a></span>';
//var selectPTwo = '<span class="CourseLinkSelected"><a href="javascript: void pTwo();">' + pageTwo + '</a></span>';
//var unselectPTwo = '<span class="CourseLink"> <a href="javascript: void pTwo();" >' + pageTwo + '</a></span>';
var selectPThree = '<span class="CourseLinkSelected"><a href="javascript: void pThree();">' + pageThree + '</a></span>';
var unselectPThree = '<span class="CourseLink"> <a href="javascript: void pThree();" >' + pageThree + '</a></span>';



function pOne() { 
	document.getElementById('PONESpan').innerHTML = selectPOne;
//  	document.getElementById('PTWOSpan').innerHTML = unselectPTwo;
  	document.getElementById('PTHREESpan').innerHTML = unselectPThree;
	loadUrl( pageOne + '.html' );
	}

//function pTwo() {
//	document.getElementById('PONESpan').innerHTML = unselectPOne;
//  	document.getElementById('PTWOSpan').innerHTML = selectPTwo;
//  	document.getElementById('PTHREESpan').innerHTML = unselectPThree;
//	loadUrl( pageTwo + '.html' ); 
//	}

function pThree() {
	document.getElementById('PONESpan').innerHTML = unselectPOne;
//  	document.getElementById('PTWOSpan').innerHTML = unselectPTwo;
  	document.getElementById('PTHREESpan').innerHTML = selectPThree;
	loadUrl( pageThree + '.html' ); 
	}

function clearAll() { 
	document.getElementById('PONESpan').innerHTML = unselectPOne;
//  	document.getElementById('PTWOSpan').innerHTML = unselectPTwo;
  	document.getElementById('PTHREESpan').innerHTML = unselectPThree;
	loadUrl( 'announcement.html' ); 
	}

//function mathF() { loadUrl( 'mathF.html' ); }