<s>[INST] Now, give a code with the same functionality, but made in C#. [/INST] using System.IO;
using iTextSharp.text.pdf;

// Open the first PDF file
PdfReader pdf1 = new PdfReader("file1.pdf");

// Open the second PDF file
PdfReader pdf2 = new PdfReader("file2.pdf");

// Create a new PDF file to write the merged content
using (FileStream output = new FileStream("merged.pdf", FileMode.Create))
{
    using (Document document = new Document())
    {
        using (PdfCopy copy = new PdfCopy(document, output))
        {
            document.Open();
            // Add the pages of the first PDF file
            for (int i = 1; i <= pdf1.NumberOfPages; i++)
            {
                copy.AddPage(copy.GetImportedPage(pdf1, i));
            }

            // Add the pages of the second PDF file
            for (int i = 1; i <= pdf2.NumberOfPages; i++)
            {
                copy.AddPage(copy.GetImportedPage(pdf2, i));
            }
        }
    }
}</s>