C# Encrypt / Decrypt File with XOR

FileXor.cs

using System.IO;

void EncryptFile(string inputFile, string outputFile)
{
    using (var fin = new FileStream(inputFile, FileMode.Open))
    using (var fout = new FileStream(outputFile, FileMode.Create))
    {
        byte[] buffer = new byte[4096];
        while (true)
        {
            int bytesRead = fin.Read(buffer);
            if (bytesRead == 0)
                break;
            EncryptBytes(buffer, bytesRead);
            fout.Write(buffer, 0, bytesRead);
        }
    }
}

const byte Secret = 183;

void EncryptBytes(byte[] buffer, int count)
{

    for (int i = 0; i < count; i++)
        buffer[i] = (byte)(buffer[i] ^ Secret);
}

EncryptFile("example.png", "example-encrypted.png");
EncryptFile("example-encrypted.png", "example-original.png");