function changeSchReg() {
  var rselect = document.getElementById('schreg');
  var rselectedIndex = rselect.selectedIndex;
  var schreg = rselect.options[rselectedIndex].value;

  var x = new MyAjax('statusid', 'HTML');
  x.get('/search/ssearch.php?action=chreg&reg='+schreg, function(s){
    var sselect = document.getElementById('school');
    sselect.options.length = 0;
    var schools = eval('(' + s + ')');
    for (schid in schools) {
      if (schid == 'toJSONString') {
        continue;
      }
      var opt = document.createElement('OPTION');
      opt.value = schid;
      opt.text = schools[schid];
      sselect.options.add(opt);
    }
  });
}

function changeSpecCls() {
  var cselect = document.getElementById('speccls');
  var cselectedIndex = cselect.selectedIndex;
  var speccls = cselect.options[cselectedIndex].value;

  var x = new MyAjax('statusid', 'HTML');
  x.get('/search/ssearch.php?action=chcls&cls='+speccls, function(s){
    var cselect = document.getElementById('spec');
    cselect.options.length = 0;
    var specs = eval('(' + s + ')');
    for (specid in specs) {
      if (specid == 'toJSONString') {
        continue;
      }
      var opt = document.createElement('OPTION');
      opt.value = specid;
      opt.text = specs[specid];
      cselect.options.add(opt);
    }
  });
}