Hi all,

Could you please clarify statement 'Isset' in BOD as query below?

For the source code in LN studio, owner has been coding to use 'On Get Hook' function and select the data from database.
After system select the data, check 'Len' and used 'Isset' statement.

select tipcf520.copt:copt.build
from tipcf520
where tipcf520._index2 = {"BUILD",:"6322"}
selectdo
selectempty
copt.build = ""
endselect

if len( trim$(copt.build) ) = 0 then
o.Build = ""
io.Build.isSet = false
endif

When system cannot get 'copt.build', XML file wasn't show tag for <Build></Build> (disappear from file).
So, please help me to explain 'io.Build.isSet = false' that statement will disable tag <Build></Build> from XML file right ?

Many thanks,