var httpReq = false;
if (window.XMLHttpRequest) { // Mozilla/Safari
  httpReq = new XMLHttpRequest();
} else if (window.ActiveXObject) { // IE
  httpReq = new ActiveXObject("Microsoft.XMLHTTP");
}

function changeLargePhoto(idph) {
  httpReq.open('POST', "ajax.php?file=changeLargePhoto&idph=" + idph, true);
  try {
    httpReq.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    httpReq.onreadystatechange = function() {
      if (httpReq.readyState == 4) {
        document.getElementById('id_photo_large').innerHTML = httpReq.responseText;
      }
    }
    httpReq.send(null);
  } catch (e) {
     // alert("ho-ho-hooo");
  }
}