Dim l1s As List(Of String) = dt.GetValues("列1", "列1 Is Not Null")
Dim l2s As List(Of String) = dt.GetValues("列2", "列2 Is Not Null")
if l2s.count > 0
for each s1 as string in l1s
for each s2 as string in l2s
lst.add(s1 & s2)
next
next
l1s.clear
l1s.addrange(lst)
lst.clear
end if
Dim l3s As List(Of String) = dt.GetValues("列3", "列3 Is Not Null")
if l3s.count > 0
for each s1 as string in l1s
for each s3 as string in l3s
lst.add(s1 & s3)
next
next
next
if l1s.count > 0 andalso lst.count = 0 then
lst.addrange(l1s)
end if
for each s as string in lst
output.show(s)
next