var xmlHttp

function showCustomer(){
var myselectType = document.getElementById("selectType");
var myselectCompany = document.getElementById("selectCompany");
var myselectCounty = document.getElementById("selectCounty");

var myType = myselectType.value;
var myCompany = myselectCompany.value;
var myCounty = myselectCounty.value;

var str = "t="+myType+"&o="+myCompany+"&c="+myCounty;

xmlHttp=GetXmlHttpObject();
if (xmlHttp==null)
  {
  alert ("Your browser does not support AJAX!");
  return;
  } 
var url="getevent.asp";
url=url+"?"+str;
url=url+"&sid="+Math.random();
xmlHttp.onreadystatechange=stateChanged;
xmlHttp.open("GET",url,true);
xmlHttp.send(null);
}

function stateChanged() 
{ 
if (xmlHttp.readyState==4)
{ 
document.getElementById("txtHint").innerHTML=xmlHttp.responseText;
}
}

function GetXmlHttpObject()
{
var xmlHttp=null;
try
  {
  // Firefox, Opera 8.0+, Safari
  xmlHttp=new XMLHttpRequest();
  }
catch (e)
  {
  // Internet Explorer
  try
    {
    xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
    }
  catch (e)
    {
    xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
  }
return xmlHttp;
}