var grid=justep.xbl('gridStuInfo').grid;
var checkColIndex = grid.getColIndexById("calculate2");
var checkedIDs = grid.getCheckedRows(checkColIndex);
var selectedID = checkedIDs .split(',');
var data = justep.xbl("data");
if(!checkedIDs==""){
for (var i = 0; i < selectedID .length; i++) {
var rowID = selectedID.getID(i);
data.setValue('xxx', 'yyy', rowID);
}
}