grouping excel rows with EPPLUS

Question

what i need is group rows when the value of the row is the same as the previous row, the value of "B3" is the same of "B2", like this:

i´m usin c# with epplus, and i see how can i do something similar to this with the outline option, and is similar to what i want, but this option have some disadvantages, such as that which doesn´t automatically group based on values and can´t do various groups....

is it possible to do this with EPPLUS? if it´s not posible, how can i add the vba code to c#?, i try this:

  StringBuilder vbaCode = new StringBuilder();

  vbaCode.AppendLine("Sheets('Sheet1').Activate");
  vbaCode.AppendLine("Range('A1: D11').Select");
  vbaCode.AppendLine("Selection.Subtotal GroupBy:= 1, Function:= xlSum, TotalList:= Array(2, 3),Replace:= True, PageBreaks:= False, SummaryBelowData:= True");
pck.Save();

but not work, i can´t open the Excel file.

EDIT

With sugested now i try Interop with the group function, but for a extrain reason he is grouping columns not rows, this is the code:

 var ExApp = new Microsoft.Office.Interop.Excel.Application();
 Microsoft.Office.Interop.Excel.Workbooks Wbs = ExApp.Workbooks;
 Microsoft.Office.Interop.Excel.Workbook Wb = Wbs.Open(fi.FullName.ToString());
 Microsoft.Office.Interop.Excel.Sheets wss = Wb.Worksheets;
 Microsoft.Office.Interop.Excel.Worksheet Ws = (Microsoft.Office.Interop.Excel.Worksheet)wss.get_Item("Sheet1");
 Ws.Range["A6:A10"].Group();
 Ws.Outline.SummaryRow =Microsoft.Office.Interop.Excel.XlSummaryRow.xlSummaryAbove;
 ExApp.Visible = true;

Answer 1

I see this is already answered but figured I would provide an EPPlus way which you can certainly do but you do need to manually create the sum cells:

[TestMethod]
public void Row_Grouping_Test()
{
    //http://stackoverflow.com/questions/41636336/grouping-excel-rows-with-epplus

    //Throw in some data
    var datatable = new DataTable("tblData");
    datatable.Columns.AddRange(new[]
    {
        new DataColumn("Header", typeof (string)), new DataColumn("Col1", typeof (int)), new DataColumn("Col2", typeof (int)), new DataColumn("Col3", typeof (object))
    });

    for (var i = 0; i < 10; i++)
    {
        var row = datatable.NewRow();
        row[0] = $"Header {i}"; row[1] = i; row[2] = i * 10; row[3] = Path.GetRandomFileName(); datatable.Rows.Add(row);
    }

    //Create a test file
    var fi = new FileInfo(@"c:\temp\Row_Grouping_Test.xlsx");
    if (fi.Exists)
        fi.Delete();

    using (var pck = new ExcelPackage(fi))
    {
        var worksheet = pck.Workbook.Worksheets.Add("Sheet1");
        worksheet.Cells.LoadFromDataTable(datatable, false);

        worksheet.Cells["A11"].Value = "TOTAL";
        worksheet.Cells["B11"].Formula = "SUBTOTAL(9,B2:B10)";
        worksheet.Cells["C11"].Formula = "SUBTOTAL(9,C2:C10)";
        worksheet.Row(11).Style.Font.Bold = true;

        //Row Group 1 (start with 1 since row index is 1-based)
        for (var i = 1; i <= datatable.Rows.Count; i++)
            worksheet.Row(i).OutlineLevel = 1;

        pck.Save();
    }
}

Which looks like this:

Answer 2

I am not familiar with EPPLUS libary.
but you can achieve that task very easily using Microsoft.Office.Interop.Excel namespace.
and than you can do it like you do it using Vba- (using the Merge() method) note that you will need to add a reference of that namespace to your project.
here is an example:

using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Microsoft.Office.Interop.Excel;

namespace WindowsFormsApplication32
{
    public partial class Form1 : Form
    {
        public Microsoft.Office.Interop.Excel.Application ExApp;


        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
            ExApp = new Microsoft.Office.Interop.Excel.Application();
            // CREATE A NEW WORKBOOK (you can also open existing workbook using the Open() method)
            Microsoft.Office.Interop.Excel.Workbook Wb = ExApp.Workbooks.Add();
            // SET WORKSHEET
            Microsoft.Office.Interop.Excel.Worksheet Ws = Wb.Worksheets.Add();
            // MERGE CELLS (the answer to your question)
            Ws.Range["A1:G5"].Merge();
            // GROUP ROWS (the final answer to your question)
            Ws.Rows["4:7"].Group();
            ExApp.Visible = true;
        }
    }
}