var tab_id;

function getXMLHTTPRequest() {
try {
req = new XMLHttpRequest();
} catch(err1) {
  try {
  req = new ActiveXObject("Msxml2.XMLHTTP");
  } catch (err2) {
    try {
    req = new ActiveXObject("Microsoft.XMLHTTP");
    } catch (err3) {
      req = false;
    }
  }
}
return req;
}

var http = getXMLHTTPRequest();

function page(page) {
  var myurl = "data.php";
  tab_id=page;
  myRand = parseInt(Math.random()*999999999999999);
  // add random number to URL to avoid cache problems
  var modurl = myurl+"?page="+page+"&rand="+myRand;
  http.open("GET", modurl, true);
  // set up the callback function
  http.onreadystatechange = useHttpResponse;
  http.send(null);
}

function useHttpResponse() {
   if (http.readyState == 4) {
    if(http.status == 200) {
	   var mytext = http.responseText;
       document.getElementById('tabbox').innerHTML = mytext;
       
	   var nameValue = http.responseXML.getElementsByTagName("content")[0];
	   var id = http.responseXML.getElementsByTagName("id")[0];
       	   
	   var tab1="<a onClick='page(1)'><table class='tab' width=75 background='images/inactive.gif'><td align=center>BTech</td></table></a>";
	   var tab2="<a onClick='page(2)'><table class='tab' width=75 background='images/inactive.gif'><td align=center>MTech</td></table></a>";
	   var tab3="<a onClick='page(3)'><table class='tab' width=75 background='images/inactive.gif'><td align=center>MBA</td></table></a>";
	   var tab4="<a onClick='page(4)'><table class='tab' width=75 background='images/inactive.gif'><td align=center>MS</td></table></a>";
		if(tab_id==1)
		{
			document.getElementById("tab1").innerHTML = "<table class='tab' width=75 background='images/active.gif'><td align=center>BTech</td></table></a>";
			document.getElementById("tab2").innerHTML = tab2;
			document.getElementById("tab3").innerHTML = tab3;
			document.getElementById("tab4").innerHTML = tab4;
		}	
		else if(tab_id==2)
		{
			document.getElementById("tab1").innerHTML = tab1;
			document.getElementById("tab2").innerHTML = "<table class='tab' width=75 background='images/active.gif'><td align=center>MTech</td></table></a>";
			document.getElementById("tab3").innerHTML = tab3;
			document.getElementById("tab4").innerHTML = tab4;
		}	
		else if(tab_id==3)
		{
			document.getElementById("tab1").innerHTML = tab1;
			document.getElementById("tab2").innerHTML = tab2;
			document.getElementById("tab3").innerHTML = "<table class='tab' width=75 background='images/active.gif'><td align=center >MBA</td></table></a>";
			document.getElementById("tab4").innerHTML = tab4;
		}	
		else 
		{
			document.getElementById("tab1").innerHTML = tab1;
			document.getElementById("tab2").innerHTML = tab2;
			document.getElementById("tab3").innerHTML = tab3;
			document.getElementById("tab4").innerHTML = "<table class='tab' width=75 background='images/active.gif'><td align=center >MS</td></table></a>";
		}	
	}
  } else {
  document.getElementById('tabbox').innerHTML = '<img src="anim.gif">';
  //document.getElementById('tab1').innerHTML='Open';
  }
}