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 selectMNAS = '<span class="CourseLinkSelected"><a href="javascript: void MNAS();">MNAS</a></span>';
var unselectMNAS = '<span class="CourseLink"> <a href="javascript: void MNAS();" >MNAS</a></span>';
var selectMR12 = '<span class="CourseLinkSelected"><a href="javascript: void MR12();">MR12</a></span>';
var unselectMR12 = '<span class="CourseLink"> <a href="javascript: void MR12();" >MR12</a></span>';
var selectMR12H = '<span class="CourseLinkSelected"><a href="javascript: void MR12H();">MR12H</a></span>';
var unselectMR12H = '<span class="CourseLink"> <a href="javascript: void MR12H();" >MR12H</a></span>';



function MNAS() { 
	document.getElementById('MNASSpan').innerHTML = selectMNAS;
  	document.getElementById('MR12Span').innerHTML = unselectMR12;
  	document.getElementById('MR12HSpan').innerHTML = unselectMR12H;
	loadUrl( 'MNAS.html' );
	}

function MR12() {
	document.getElementById('MNASSpan').innerHTML = unselectMNAS;
  	document.getElementById('MR12HSpan').innerHTML = unselectMR12H;
  	document.getElementById('MR12Span').innerHTML = selectMR12;
	loadUrl( 'MR12.html' ); 
	}

function MR12H() {
	document.getElementById('MNASSpan').innerHTML = unselectMNAS;
  	document.getElementById('MR12Span').innerHTML = unselectMR12;
  	document.getElementById('MR12HSpan').innerHTML = selectMR12H;
	loadUrl( 'MR12H.html' ); 
	}
//function mathF() { loadUrl( 'mathF.html' ); }