Try
CFisc = DataReader.GetString(0)
If CFisc = 0 Then
Throw New InvalidOperationException
End If
cmd1.CommandText = "SELECT DSCOGNOME, DSNOME, POSIZIONE FROM XXX WHERE CDFISC = '" & CFisc & "'"
DataReader = cmd1.ExecuteReader()
DataReader.Read()
Cogn_Valu = DataReader.GetString(0)
Nome_Valu = DataReader.GetString(1)
Pos_Valu = DataReader.GetString(2)
cmd2.CommandText = "SELECT DSCOGNOME, DSNOME, CDFISC, POSIZIONE FROM XXX, YYY WHERE POSCOH = '" & Pos_Valu & "' AND POSCOD = POSIZIONE "
DataReader = cmd2.ExecuteReader()
DataGrid1.DataSource = DataReader
DataGrid1.DataBind()
DataReader.Close()
Catch ex As Exception
lblError.Text() = "Utente non riconosciuto"
End Try