var XmlHttp;

function GetXmlHttpObject() {
   var XmlHttp = null;
   try {
      XmlHttp = new XMLHttpRequest();
   } catch (e) {
      try {
         XmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
      } catch (e) {
         XmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
      }
   }
   return XmlHttp;
}

function StateChanged() {
   if (XmlHttp.readyState == 4 || XmlHttp.readyState == "complete") {
      document.getElementById("CalcSum").innerHTML = XmlHttp.responseText;
   }
}
function ShowSum(url, params) {
   XmlHttp = GetXmlHttpObject();
   if (XmlHttp == null)
      return;
   XmlHttp.onreadystatechange = StateChanged; 
   XmlHttp.open('POST', url, true);
   XmlHttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
   XmlHttp.setRequestHeader("Content-length", params.length);
   XmlHttp.setRequestHeader("Connection", "close");
   XmlHttp.send(params);
}

function GetInfo() {
   var str = "size1=" + escape(encodeURI(document.getElementById("size1").value)) +              "&size2=" + escape(encodeURI(document.getElementById("size2").value)) + 			 "&material=" + escape(encodeURI(document.getElementById("material").value)) + 
             "&slop=" + escape(encodeURI(document.getElementById("slop").value)) + 
             "&difficulty=" + escape(encodeURI(document.getElementById("difficulty").value)) +
			 "&existing=" + escape(encodeURI(document.getElementById("existing").value)) +
			 "&sky=" + escape(encodeURI(document.getElementById("sky").value)) +
			 "&ridge=" + escape(encodeURI(document.getElementById("ridge").value)) +
			 "&floor=" + escape(encodeURI(document.getElementById("floor").value)) +
			 "&chim=" + escape(encodeURI(document.getElementById("chim").value));

   ShowSum('http://www.roofingcalculator.org/scripts/getcalc-nodrop.php', str);
}