sql server - VB.Net Dataset checking null -


using vb.net , sql server

so dataset this:

dim ds3 new focusdatasettableadapters.gajitableadapter

and want item in dataset array. dataset empty now.. try..

dim smp new list(of string)()   try   = 0 ds3.getdata.count - 1    if (ds3.getdata.rows(0).item(3) nothing)     smp.add("0")   end if     next       catch ex exception         = - 1          end try

so want is.. if database null/empty add "0" array. everytime run code gives me error state there row @ current position (0)...

your code should (maybe necessary more modification - snippet cannot tested): 

try   dim tbl datatable=ds3.getdata()   = 0 tbl.rows.count - 1    if (tbl.rows(i).item(3) dbnull.value)     smp.add("0")    end if    next  catch ex exception         = - 1 'rather strange , causes endless loop  end try

you should aware getdata method returns datatable , want iterate it. reconsider errorhandling!


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