using RL.ExcelFileGenerator;

// ...

public class Product
{
	[ExcelColumn("Product Id", 4)]
	public int Id { get; set; }

	public string Code { get; set; }

	[ExcelColumn("Product Name", 1)]
	public string Name { get; set; }

	[ExcelColumn("Product Price", 3, NumberingFormatString = "#,##0.00")]
	public decimal? Price { get; set; }

	[ExcelColumn("Product Discount", 2)]
	public float Discount { get; set; }

	[ExcelColumn("Available Date", 5, NumberFormatId = 22)]
	public DateTime AvailableDate { get; set; }

	[ExcelColumn("Is Offline", 6)]
	public bool IsOffline { get; set; }
}

using RL.ExcelFileGenerator;
using System.IO;

// ...

class Program
{
	static void Main(string[] args)
	{
		List<Product> products = new List<Product>(3);
		products.Add(new Product()
			{
				Code = "P_A",
				Discount = 0.1F,
				Id = 1,
				Name = "ABC",
				Price = 6000.85m,
				AvailableDate = DateTime.Now
			});
		products.Add(new Product()
		{
			Code = "P_B",
			Discount = 0.2F,
			Id = 2,
			Name = "XYZ",
			Price = 5500.50m,
			AvailableDate = DateTime.Now.AddDays(-3),
			IsOffline = true
		});
		products.Add(new Product()
			{
				Code = "P_C",
				Discount = 0.22F,
				Id = 3,
				Name = "123",
				Price = null,
				AvailableDate = DateTime.Now.AddDays(-3),
				IsOffline = true,
				NullableBool = true
			});
		products.Add(new Product()
		{
			Code = "P_D",
			Discount = 0.35F,
			Id = 4,
			Name = "456",
			Price = 5800.0m,
			AvailableDate = DateTime.Now.AddDays(-5)
		});

		string fileName = Path.Combine(Directory.GetCurrentDirectory(), "Test.xlsx");

		// create .xlsx file as MemoryStream
		using (MemoryStream ms = ExcelGenerator.CreateStream(products, "Products"))
		{
			using (FileStream fs = File.Create(fileName))
			{
				ms.WriteTo(fs);
			}
		}

		// create .xlsx file
		//ExcelGenerator.CreateFile(products, "Products", fileName);
	}
}