if (typeof XMLHttpRequest == "undefined") {
  XMLHttpRequest = function() {
    try { return new ActiveXObject("Msxml2.XMLHTTP.6.0"); }
      catch(e) {}
    try { return new ActiveXObject("Msxml2.XMLHTTP.3.0"); }
      catch(e) {}
    try { return new ActiveXObject("Msxml2.XMLHTTP"); }
      catch(e) {}
    try { return new ActiveXObject("Microsoft.XMLHTTP"); }
      catch(e) {}
    throw new Error("This browser does not support XMLHttpRequest.");
  };
}