function getXmlHttp() {
  var xmlhttp;
  try {
    xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
  } catch (e) {
    try {
      xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
    } catch (E) {
      xmlhttp = false;
    }
  }
  if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
    xmlhttp = new XMLHttpRequest();
  }
  return xmlhttp;
 }
 
 function sendInvite() {
  var f = document.getElementById('inviteForm');
  
  var xmlHttp = getXmlHttp();
  xmlHttp.open('POST', '../sendInvitation.php', false);
  xmlHttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
  
  var params = 'invite=1';
  var name = f.elements['name'];
  var email = f.elements['email'];
  var messag = f.elements['messag'];
  params += '&name' + '=' + name + '&email' + '=' + email + '&messag' + '=' + messag;
  xmlHttp.send(params);
  
  if (xmlHttp.status == 200) return true;
  
  alert('Ошибка...' + params);
 // return false;
 }
 
 function doSend() {
  if (sendInvite()) {
   alert('Приглашения отосланы...');
   return true;
  }
  else return false;
 }