/*
 * Riempie una select dinamicamente.
 * target_element: nome dell'id della select da riempire
 * url_page: nome dello script php
 * param_str: stringa di parametri da passare allo script
 *
 * Lo script php deve restituire un testo formattato cos“:
 * 	[
 * 	{text:'testo',value:'valore'},
 * 	{text:'testo',value:'valore'},
 * 	{text:'testo',value:'valore'},
 * 	...
 * 	]
 * 
 **/
function FillSelect(target_element,url_page,param_str ) {

    var fnCarica = function (oGet)
    {
	objSelect = document.getElementById(target_element) ;
	var sJSON = oGet.responseText;
	var oJSON = eval(sJSON);
	
	for( nOpt=0;nOpt=objSelect.options.length;nOpt++) {   objSelect.options[0] = null   };
	
	for( nOpt=0;nOpt<oJSON.length;nOpt++)
	{
		var newOpt = new Option( oJSON [nOpt].text , oJSON [nOpt].value );
		if (oJSON [nOpt].selected) {
			 newOpt.selected=true;
	}
	objSelect.options[objSelect.options.length] = newOpt;
	};
    };
    new XHConn().connect(url_page, 'GET', param_str , fnCarica);
}


/** XHConn - Simple XMLHTTP Interface - bfults@gmail.com - 2005-04-08        **
 ** Code licensed under Creative Commons Attribution-ShareAlike License      **
 ** http://creativecommons.org/licenses/by-sa/2.0/                           **/
function XHConn()
{
  var xmlhttp, bComplete = false;
  try { xmlhttp = new ActiveXObject("Msxml2.XMLHTTP"); }
  catch (e) { try { xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); }
  catch (e) { try { xmlhttp = new XMLHttpRequest(); }
  catch (e) { xmlhttp = false; }}}
  if (!xmlhttp) return null;
  this.connect = function(sURL, sMethod, sVars, fnDone)
  {
    if (!xmlhttp) return false;
    bComplete = false;
    sMethod = sMethod.toUpperCase();

    try {
      if (sMethod == "GET")
      {
        xmlhttp.open(sMethod, sURL+"?"+sVars, true);
        sVars = "";
      }
      else
      {
        xmlhttp.open(sMethod, sURL, true);
        xmlhttp.setRequestHeader("Method", "POST "+sURL+" HTTP/1.1");
        xmlhttp.setRequestHeader("Content-Type",
          "application/x-www-form-urlencoded");
      }
      xmlhttp.onreadystatechange = function(){
        if (xmlhttp.readyState == 4 && !bComplete)
        {
          bComplete = true;
          fnDone(xmlhttp);
        }};
      xmlhttp.send(sVars);
    }
    catch(z) { return false; }
    return true;
  };
  return this;
}