function getXMLHTTP() { //fuction to return the xml http object
 var xmlhttp=false;
 try{xmlhttp=new XMLHttpRequest();}
 catch(e){
  try{xmlhttp= new ActiveXObject("Microsoft.XMLHTTP");}
  catch(e){
   try{req = new ActiveXObject("Msxml2.XMLHTTP");}
   catch(e1){xmlhttp=false;}
  }
 }
 return xmlhttp;
}


function getCidade(strURL) {
 var req = getXMLHTTP();
 if (req) {
  req.onreadystatechange = function() {
   if (req.readyState == 4) {
    // only if "OK"
    if (req.status == 200) {
     document.getElementById('cidadediv').innerHTML=req.responseText;
    } else {
     alert("Houve um problema ao utilizar o XMLHTTP:\n" + req.statusText);
    }
   }
  }
  req.open("GET", strURL, true);
  req.send(null);
 }
}