Copy worksheet in Excel

NPOI
Spire.XLS
Download Sample Code

using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace NPOI
{
    class Program
    {
        static void Main(string[] args)
        {
            //Load workbook
            IWorkbook workbook = new XSSFWorkbook(new FileStream("../../../Data/Sample.xlsx", FileMode.Open));

            //Get the first worksheet
            ISheet sheet = workbook.GetSheetAt(0);

            //Copy to a new sheet
            sheet.CopySheet("copied sheet", true);

            //Save the file
            FileStream file = File.Create("Copied.xlsx");
            workbook.Write(file);
            file.Close();

            //Launch
            System.Diagnostics.Process.Start("Copied.xlsx");
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Spire.Xls;

namespace Spire.XLS
{
    class Program
    {
        static void Main(string[] args)
        {
            //Load workbook
            Workbook workbook = new Workbook();
            workbook.LoadFromFile("../../../Data/Sample.xlsx");

            //Get the first worksheet
            Worksheet sheet = workbook.Worksheets[0];

            //Create a new worksheet
            Worksheet newSheet = workbook.CreateEmptySheet("Copied sheet");

            //Copy worksheet to the new added worksheet
            newSheet.CopyFrom(sheet);

            //Save and Launch
            workbook.SaveToFile("Copied.xlsx", ExcelVersion.Version2013);
            System.Diagnostics.Process.Start("Copied.xlsx");
        }
    }
}

CopyWorksheet.zip