var xmlhttp10 , xmlhttp2;
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;
}

function show_city(state)
{
xmlhttp10=getxmlhttpobject()
var state1=document.getElementById(state).value;

var query="state1="+state1+"&state="+state;
xmlhttp10.onreadystatechange=function(){
if (xmlhttp10.readyState==4)
 {
  document.getElementById(state+"_div").innerHTML=xmlhttp10.responseText;
  }
 }
 
xmlhttp10.open("GET","action_page.php?action=show_city&"+query,true)
xmlhttp10.send(null)
}