var xmlHttp
function showcity(str)
{  //alert(str);
xmlHttp=GetXmlHttpObject()

if (xmlHttp==null)
{
alert ("Browser does not support HTTP Request")
return
} 

var url="city.php"
url = url+"?stateid="+str
xmlHttp.onreadystatechange=countyChange 
xmlHttp.open("GET",url,true)
xmlHttp.send(null)
}

function countyChange() 
{ 
if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
{ 
//alert(xmlHttp.responseText);

	

document.getElementById("citydiv").innerHTML=xmlHttp.responseText;

}
} 

function GetXmlHttpObject()
{ 
var objXMLHttp=null
if (window.XMLHttpRequest)
{
objXMLHttp=new XMLHttpRequest()
}
else if (window.ActiveXObject)
{
objXMLHttp=new ActiveXObject("Microsoft.XMLHTTP")
}
return objXMLHttp
}