var reg=new RegExp("[\n]+", "g");
var reg2=new RegExp("[|]+", "g");

function getHTTPObject() {
  try { return new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) {}
   try { return new ActiveXObject("Microsoft.XMLHTTP"); } catch (e) {}
   try { return new XMLHttpRequest(); } catch(e) {}
   alert("XMLHttpRequest not supported, please update your browser.");
   return null;
}

function GetDropDown(dropdown,element_id) {
	var http = getHTTPObject(); // We create the HTTP Object
	var URL = "index.php?go=dropdown&";
	if (dropdown == 'region')
	{
		//document.getElementById("deplist").length = 0;
		var country = document.getElementById("countrylist")[document.getElementById("countrylist").selectedIndex].value;
		URL += "do=region&country=" + escape(country);
	}

	if (dropdown == 'departement')
	{
		var country = document.getElementById("countrylist")[document.getElementById("countrylist").selectedIndex].value;
		var region = document.getElementById("regionlist")[document.getElementById("regionlist").selectedIndex].value;
		URL += "do=departement&country=" + escape(country) + "&region=" + escape(region);
	}
	if (dropdown == 'city')
	{
		var region = 0;
		var departement = 0;
		var country = document.getElementById("countrylist")[document.getElementById("countrylist").selectedIndex].value;
		URL += "do=city&country=" + escape(country);
	}
	if (dropdown == 'district')
	{
		var country = document.getElementById("countrylist")[document.getElementById("countrylist").selectedIndex].value;
		var city = document.getElementById("citylist")[document.getElementById("citylist").selectedIndex].value;
		URL += "do=district&country=" + escape(country) + "&city=" + escape(city);
	}
		http.open("GET", URL  , true);
		http.onreadystatechange = function() {
				 if (http.readyState == 4) {
			    var result = http.responseText;
					var tableau=result.split(reg);
					document.getElementById(element_id).length = 0;
					for (var i=0; i<tableau.length; i++) 
					{
					  if (tableau[i])
					  {
						  var subtab = tableau[i].split(reg2);
						  var elOptNew = document.createElement('option');
						  elOptNew.text = subtab[1];
						  elOptNew.value = subtab[0];
						  var elSel = document.getElementById(element_id);
						  try {
						    elSel.add(elOptNew, null); // standards compliant; doesn't work in IE
						  }
						  catch(ex) {
						    elSel.add(elOptNew); // IE only
						  }
						}
					}
			  }
			}
		http.setRequestHeader("Content-Type","text/html; charset=utf-8"); 
		http.send(null);
}