Specified cast is not valid - when trying to retusn sum

[Olivera_Kalinic (Olivera Kalinić)]

I am trying to return sum of column “BROJ APLIKACIJA” from data table (all is printed well after extracting from excel)

but getting error “Specified cast is not valid”

I’m using
tabelaPlasiraniTotal.AsEnumerable().Sum(Function(r) r.Field(Of Double)(“BROJ APLIKACIJA”)).ToString

[Gokul001 (Gokul Balaji)]

Hi @Olivera_Kalinic

Try this expression

(From d in dtData.AsEnumerable Where Not (isNothing(d("BROJ APLIKACIJA")) OrElse String.IsNullorEmpty(d("BROJ APLIKACIJA").toString.Trim)) Select v = CDbl(d("BROJ APLIKACIJA").toString.Trim)).Sum(Function (x) x)

Regards
Gokul

[Gangadhar_Athili]

DT.Asenumerable.sum(Function(r) CInt(“0”+r(1).Tostring))

[Olivera_Kalinic (Olivera Kalinić)]

I tryed, but getting the error below

[Olivera_Kalinic (Olivera Kalinić)]

This one also returns error

[Gangadhar_Athili]

DT.Asenumerable.sum(Function(r) CInt(“0”+r(1).Tostring)).Tostring

[Gokul001 (Gokul Balaji)]

Try with this expression

(From d in dtData.AsEnumerable Where Not (isNothing(d(1)) OrElse String.IsNullorEmpty(d(1).toString.Trim)) Select v = CDbl(d(1).toString.Trim)).Sum(Function (x) x)

d(1) → Is the column index

Regards
Gokul

[Olivera_Kalinic (Olivera Kalinić)]

Thank you for your support, in the meanwhile I find solution by iterating through all table rows and making sum of wanted column items.