var XMLHttpRequestObject = false;

if (window.XMLHttpRequest) {
  XMLHttpRequestObject = new XMLHttpRequest(); } 
else if (window.ActiveXObject) {
  XMLHttpRequestObject = new ActiveXObject("Microsoft.XMLHTTP"); }
  
function getCANTS(codprov) {
  var url = 'getcantones.php';
  url = url + "?p=" + codprov;
  XMLHttpRequestObject.open("GET", url); 
  XMLHttpRequestObject.onreadystatechange = function()
  {
  if (XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200) {
    var texto = XMLHttpRequestObject.responseText;
    cadena = unescape(texto);
    cadenafinal = cadena.replace(/\+/gi," ");
    document.getElementById('txtCANT').innerHTML = cadenafinal;
    }
  }
  XMLHttpRequestObject.send(null);
}