Creating Excel Files in C# Without Microsoft Office: A Guide Using EPPlus Library

 To create an Excel (.XLS and .XLSX) file in C# without installing Microsoft Office, you can make use of third-party libraries that provide Excel manipulation capabilities. One popular library is EPPlus, which is a free open-source library for creating and manipulating Excel files in C#. Here's how you can use EPPlus to create an Excel file:

1. Install EPPlus: Use NuGet Package Manager to install the EPPlus library into your C# project. You can do this by right-clicking on your project in Visual Studio, selecting "Manage NuGet Packages," and searching for "EPPlus" to install it.

2. Import EPPlus namespace: In your C# code file, import the EPPlus namespace using the following statement:

using OfficeOpenXml;

3. Create a new Excel file and add data: Use the EPPlus library to create an Excel package, add worksheets, and populate them with data. Here's an example that creates a simple Excel file with a single worksheet and some data:

// Create a new Excel package
using (ExcelPackage package = new ExcelPackage())
{
    // Add a new worksheet
    ExcelWorksheet worksheet = package.Workbook.Worksheets.Add("Sheet1");

    // Add data to the worksheet
    worksheet.Cells["A1"].Value = "Hello";
    worksheet.Cells["B1"].Value = "World!";

    // Save the Excel file
    package.SaveAs(new FileInfo("path_to_your_excel_file.xlsx"));
}

In the above code, replace "path_to_your_excel_file.xlsx" with the desired file path and name for your Excel file. This will create an Excel file with the specified data.

4. Optional: Save as .XLS format (Excel 97-2003): By default, EPPlus saves the Excel file in .XLSX format (Excel 2007 and later). If you specifically need to save it in .XLS format (Excel 97-2003), you can use a different library like NPOI, which supports older Excel formats.

By following these steps and utilizing EPPlus or similar libraries, you can create Excel files (.XLSX format) in C# without the need to install Microsoft Office.