Using AJAX to validate on Change

Activator - on change of select list
onfocus - backs up value of select list

function validcalcbasis (itemid){

var src_node_id = document.getElementsByName("f03");
var str=itemid.id;
var i = str.substr(4,4) ;
i = parseFloat(i) - 1;
//get the array value

var get = new htmldb_Get(null,$x('pFlowId').value,'APPLICATION_PROCESS=VALIDCALCBASIS',0);
get.add('CALC_BASIS_ID',itemid.value);
get.add('NODE_TYPE_ID',src_node_id[i].value);
gReturn = get.get();


if(gReturn != ""){
itemid.value = document.getElementById('P7019_PREV_SELECT').value;
alert(gReturn);
}
get = null;

}