var xmlHttp1

function showmodel(str)
{ 
document.getElementById("model_select").innerHTML="<select style='color:#000000; font-size:9px; width:140px;' name='network'><option value='0'>Loading...</option></select>" 
xmlHttp1=GetXmlHttpObject()
if (xmlHttp1==null)
 {
 alert ("Browser does not support HTTP Request")
 return
 }
var url1="getmodel_ajax.php"
url1=url1+"?manufacturer="+str
url1=url1+"&sid="+Math.random()
xmlHttp1.onreadystatechange=stateChanged 
xmlHttp1.open("GET",url1,true)
xmlHttp1.send(null)
}

function stateChanged() 
{ 
if (xmlHttp1.readyState==4 || xmlHttp1.readyState=="complete")
 { 
 document.getElementById("model_select").innerHTML=xmlHttp1.responseText 
 } 
}

function GetXmlHttpObject()
{
var xmlHttp1=null;
try
 {
 // Firefox, Opera 8.0+, Safari
 xmlHttp1=new XMLHttpRequest();
 }
catch (e)
 {
 //Internet Explorer
 try
  {
  xmlHttp1=new ActiveXObject("Msxml2.XMLHTTP");
  }
 catch (e)
  {
  xmlHttp1=new ActiveXObject("Microsoft.XMLHTTP");
  }
 }
return xmlHttp1;
}