Date Field value exporting to excell

 if date value is exported with time and if the date value is null but in excell getting value use follow below to conver date to str.

str documentDate;

if(ledgerJournalTrans.DocumentDate != dateNull())
{
documentDate = date2str(ledgerJournalTrans.DocumentDate,321,DateDay::Digits2,DateSeparator::Slash,DateMonth::Digits2,DateSeparator::Slash,DateYear::Digits4);
}
if(ledgerJournalTrans.DocumentDate == dateNull())
{
documentDate = date2str(dateNull(),321,DateDay::Digits2,DateSeparator::Slash,DateMonth::Digits2,DateSeparator::Slash,DateYear::Digits4);
}
cell = cells.item(Row,30);
cell.value(documentDate);