function ajax(){
   try{
      xml=new XMLHttpRequest();
   }catch(e){
      try{
         xml=new ActiveXObject("Msxml2.XMLHTTP");
      }catch(e){
         try{
            xml=new ActiveXObject("Microsoft.XMLHTTP");
         }catch(e){ return false;}
      }
   }
   return xml;
}
function classresponse(){
   if(xml.readyState==4)
     document.getElementById("class").innerHTML=xml.responseText;
}
function classes(){
   xml=ajax();
   xml.onreadystatechange=classresponse;
   xml.open('GET',"class.php?get=class",true);
   xml.send(null);
}
function timeresponse(){
   if(xml.readyState==4)
     document.getElementById("time").innerHTML=xml.responseText;
}
function time(e){
   xml=ajax();
   xml.onreadystatechange=timeresponse;
   xml.open('GET',"class.php?get=time&class="+e,true);
   xml.send(null);
}
function errorresponse(){
   if(xml.readyState==4)
        document.getElementById("error").innerHTML=xml.responseText;
}
function error(){
   xml=ajax();
   xml.onreadystatechange=errorresponse;
   xml.open('POST',"error.php",true);
   var elements=document.getElementById("regform").elements;
   var param="";
   for(var x=0;x<elements.length;x++)
     param+=elements[x].name+"="+elements[x].value+"&";
   param=param.substr(0,param.length-1);
   xml.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
   xml.setRequestHeader("Content-length", param.length);
   xml.setRequestHeader("Connection", "close");
   xml.send(param);
   var html=document.getElementById("error").innerHTML;
   if(html=="")
     return true;
   else{
     return false;
   }
}
function validate(){
  var elements=document.getElementById("regform").elements;
  var valid=true;
  for(var x=0;x<elements.length;x++){
    if(x==0||x==2||x==5||x==6||x==7){
      if(elements[x].value==""){
        valid=false;
        elements[x].style.backgroundColor="#72A4D2";
      }else
        elements[x].style.backgroundColor="#FFFFFF";
    }
  }
  if(!valid){
    document.getElementById("error2").innerHTML="Colored fields cannot be blank";
    return false;
  }else{
    document.getElementById("error2").innerHTML="";
    return error();
  }
}