How to group rows or columns in C#.NET

EasyXLS Excel library can be used to export Excel files in C#. The library works with .NET Framework or .NET Core platform.

Step 1: Download EasyXLS Excel Library for .NET

To download the trial version of EasyXLS Excel Library, press the below button:

Download EasyXLS™ Excel Library for C#

If you already own a license key, you may login and download EasyXLS from your account.

Install the downloaded EasyXLS installer for v8.6 or earlier.

Step 2: License file setup

Step required for EasyXLS v9.0 or later.

If you are using a trial, generate a trial license file from EasyXLS trials page. The trial license is valid for 30-days.

If you own a license key, you may login to the account that purchased the license and generate the license file from:

Setup the license file into your project using these guidelines.

Step 3: Create a C# project

If don't have a project, create one as ASP.NET web application, windows forms app, console application, class library or service.

Step 4: Include EasyXLS library into project

EasyXLS.dll must be added as reference to your project. EasyXLS.dll can be found:
- Inside the downloaded archive at Step 1 for EasyXLS v9.0 or later
- Under installation path for EasyXLS v8.6 or earlier, in "Dot NET version" folder.

Add EasyXLS reference

Step 5: Run C# code that groups data in Excel sheet

Execute the following C# code that groups data on the first sheet of an Excel file on two outline levels.

/* --------------------------------------------------------------------------
 * Tutorial 17
 * This tutorial shows how to create an Excel file with groups on rows in C#.
 * The Excel file has two worksheets. The first one is full with data and
 * contains the data groups.
 * -------------------------------------------------------------------------- */

using System;
using EasyXLS;
using EasyXLS.Constants;

public class Tutorial17
    static void Main()
        Console.WriteLine("Tutorial 17\n----------\n");

        // Create an instance of the class that exports Excel files having two sheets
        ExcelDocument workbook = new ExcelDocument(2);
        // Set the sheet names
        workbook.easy_getSheetAt(0).setSheetName("First tab");
        workbook.easy_getSheetAt(1).setSheetName("Second tab");

        // Get the table of data for the first worksheet
        ExcelTable xlsFirstTable = ((ExcelWorksheet)workbook.easy_getSheetAt(0)).easy_getExcelTable();

        // Add data in cells for report header
        for (int column=0; column<5; column++)
            xlsFirstTable.easy_getCell(0,column).setValue("Column " + (column + 1)); 

        // Add data in cells for report values
        for (int row=0; row<25; row++)
            for (int column=0; column<5; column++)
                xlsFirstTable.easy_getCell(row+1,column).setValue("Data " + (row + 1) + ", " + (column + 1)); 

        // Set column widths
        xlsFirstTable.setColumnWidth(0, 70);
        xlsFirstTable.setColumnWidth(1, 100);
        xlsFirstTable.setColumnWidth(2, 70);
        xlsFirstTable.setColumnWidth(3, 100);
        xlsFirstTable.setColumnWidth(4, 70);

        // Group rows and format A1:E26 cell range
        ExcelDataGroup xlsFirstDataGroup = new ExcelDataGroup("A1:E26", DataGroup.GROUP_BY_ROWS, false);
        xlsFirstDataGroup .setAutoFormat(new ExcelAutoFormat(EasyXLS.Constants.Styles.AUTOFORMAT_EASYXLS1));
        ((ExcelWorksheet)workbook.easy_getSheetAt(0)).easy_addDataGroup(xlsFirstDataGroup );

        // Group rows and format A2:E10 cell range, outline level two, inside previous group
        ExcelDataGroup xlsSecondDataGroup = new ExcelDataGroup("A2:E10", DataGroup.GROUP_BY_ROWS, false);
        xlsSecondDataGroup.setAutoFormat(new ExcelAutoFormat(EasyXLS.Constants.Styles.AUTOFORMAT_EASYXLS2)); 

        // Export Excel file
        Console.WriteLine("Writing file C:\\Samples\\Tutorial17 - group data in Excel.xlsx.");
        workbook.easy_WriteXLSXFile("C:\\Samples\\Tutorial17 - group data in Excel.xlsx");

        // Confirm export of Excel file
        String sError = workbook.easy_getError();
        if (sError.Equals(""))
            Console.Write("\nFile successfully created. Press Enter to Exit...");
            Console.Write("\nError encountered: " + sError + "\nPress Enter to Exit...");

        // Dispose memory


EasyXLS Excel libraries:

Excel Library for C#
full .NET version to import, export or convert Excel files
Excel Writer for C#
.NET version to create and export Excel files
Download EasyXLS™ Excel Library for C#

File formats:

Office 365
MS Excel 2021 - 2024
MS Excel 2007 - 2019
MS Excel 97 - 2003