Hi Ransome.
>> How can I code a routine to check whether the new input datas is blank or not before updating. If the datas is blank, how can I delete the blank datas and update only the lines which have valid datas at ? <<
the easiest way is to use SCATTER NAME loOriginal right after you appended a new record. Save the object in some property on the form and when you save use something like this:
SCATTER NAME loNew
IF NOT COMPOBJ(loNew,loOriginal)
ENDIF
Marcia