ByteScout Barcode Suite – VB.NET – Set custom functions with spreadsheet sdk

Home
/
Articles
/
ByteScout Barcode Suite – VB.NET – Set custom functions with spreadsheet sdk

printable version:
ByteScout-Barcode-Suite-VB-NET-Set-custom-functions-with-spreadsheet-sdk.pdf

How to set custom functions with spreadsheet sdk in VB.NET using ByteScout Barcode Suite

This code in VB.NET shows how to set custom functions with spreadsheet sdk with this how to tutorial

An easy to understand guide on how to set custom functions with spreadsheet sdk in VB.NET with this source code sample. ByteScout Barcode Suite is the set that includes three different SDK products to generate barcodes, read barcodes and read and write spreadsheets: Barcode SDK, Barcode Reader SDK and Spreadsheet SDK. It can be applied to set custom functions with spreadsheet sdk using VB.NET.

Want to quickly learn? This fast application programming interfaces of ByteScout Barcode Suite for VB.NET plus the guidelines and the code below will help you quickly learn how to set custom functions with spreadsheet sdk. This VB.NET sample code is all you need for your app. Just copy and paste the code, add references (if needs to) and you are all set! Further improvement of the code will make it more robust.

Trial version of ByteScout Barcode Suite is available for free. Source code samples are included to help you with your VB.NET app.

On-demand (REST Web API) version:
Web API (on-demand version)

On-premise offline SDK for Windows:
60 Day Free Trial (on-premise)

Module1.vb

      Imports Bytescout.Spreadsheet

Module Module1

    ' This example demonstrates the calculation of custom functions.
    Sub Main()

        ' Create Spreadsheet instance

        Dim spreadsheet As New Spreadsheet()
        spreadsheet.RegistrationName = "demo"
        spreadsheet.RegistrationKey = "demo"

        ' Load document
        spreadsheet.LoadFromFile("CustomFuncExample.xlsx")

        ' Add custom formula handler
        spreadsheet.CustomFunctionsCallback = AddressOf MyFunctions

        ' Calculate the first worksheet
        Dim worksheet = spreadsheet.Workbook.Worksheets(0)
        worksheet.Calculate()

        ' Save calculated values to neighbor cells to demonstrate custom functions are calculated
        worksheet("C2").Value = worksheet("B2").Value
        worksheet("C3").Value = worksheet("B3").Value
        worksheet("C4").Value = worksheet("B4").Value

        ' Save modified spreadsheet
        spreadsheet.SaveAs("result.xlsx")

        ' Cleanup
        spreadsheet.Dispose()

        ' Open saved spreadsheet in associated application (for demo purpose)
        Process.Start("result.xlsx")

    End Sub

    Private Function MyFunctions(ByVal funcname As String, ByVal args As Object(), ByRef handled As Boolean) As Object

        ' Handle "CUSTOMFUNC_FACTORIAL" function
        If String.Compare(funcname, "CUSTOMFUNC_FACTORIAL", StringComparison.OrdinalIgnoreCase) = 0 Then

            handled = True

            ' Compute factorial
            If args.Length > 0 Then
                Dim value As Integer = args(0)

                If value = 0 Or value = 1 Then
                    Return 1
                End If

                Dim f As Integer = 1
                For i As Integer = 1 To value
                    f = f * i
                Next

                Return f
            End If

            Return Nothing

        End If

        ' Handle "CUSTOMFUNC_SUM" function
        If String.Compare(funcname, "CUSTOMFUNC_SUM", StringComparison.OrdinalIgnoreCase) = 0 Then

            handled = True

            ' Compute the sum of values
            If args.Length > 0 Then

                Dim sum As Double

                For Each o As Object In args
                    sum = sum + o
                Next

                Return sum

            End If

            Return Nothing

        End If

        Return Nothing

    End Function

End Module