ByteScout Spreadsheet SDK – C# – Use Custom Functions

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ByteScout Spreadsheet SDK – C# – Use Custom Functions

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ByteScout-Spreadsheet-SDK-C-sharp-Use-Custom-Functions.pdf

How to use custom functions in C# using ByteScout Spreadsheet SDK

Tutorial on how to use custom functions in C#

Learn how to use custom functions in C# with this source code sample. ByteScout Spreadsheet SDK: the SDK to create, read, modify and calculate spreadsheets. Formula calculations are supported, import and export to and from JSON, CSV, XML, databases, arrays. It can use custom functions in C#.

C# code samples for C# developers help to speed up coding of your application when using ByteScout Spreadsheet SDK. In order to implement the functionality, you should copy and paste this code for C# below into your code editor with your app, compile and run your application. Test C# sample code examples whether they respond your needs and requirements for the project.

Download free trial version of ByteScout Spreadsheet SDK from our website with this and other source code samples for C#.

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Program.cs

      using System;
using System.Diagnostics;

using Bytescout.Spreadsheet;

namespace CustomFunctions
{
    /// <summary>
    /// This example demonstrates the calculation of custom functions.
    /// </summary>
    class Program
    {
        static void Main(string[] args)
        {
            // Create Spreadsheet instance
            Spreadsheet spreadsheet = new Spreadsheet();
            spreadsheet.RegistrationName = "demo";
            spreadsheet.RegistrationKey = "demo";

            // Load document
            spreadsheet.LoadFromFile(@"CustomFuncExample.xlsx");

            // Add custom formula handler
            spreadsheet.CustomFunctionsCallback = new CustomFunctionsCallback(MyFunctions);
            
            // Calculate the first worksheet
            Worksheet 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");
        }

        public static object MyFunctions(string funcName, object[] args, ref bool handled)
        {
            // Handle "CUSTOMFUNC_FACTORIAL" function
            if (String.Compare(funcName, "CUSTOMFUNC_FACTORIAL", StringComparison.OrdinalIgnoreCase) == 0)
            {
                handled = true;

                // Compute factorial
                if (args.Length > 0)
                {
                    int value = (int)(double) args[0];

                    if (value == 0 || value == 1)
                        return 1;

                    int f = 1;
                    for (int i = 1; i <= value; i++)
                        f = f * i;

                    return f;
                }

                return null;
            }

            // Handle "CUSTOMFUNC_SUM" function
            if (string.Compare(funcName, "CUSTOMFUNC_SUM", StringComparison.OrdinalIgnoreCase) == 0)
            {
                handled = true;

                // Compute the sum of values
                if (args.Length > 0)
                {
                    double sum = 0;
                    foreach (var o in args)
                        sum += (double)o;

                    return sum;
                }

                return null;
            }

            return null;
        }
    }
}