Question

How I can convert the following methods to C# 2.0?

    private static string ToHexString(byte[] bytes)
    {
        return string.Join(string.Empty, bytes.Select(x => x.ToString("X2")).ToArray());
    }

    private static byte[] ToByteArray(string hex)
    {
        return Enumerable.Range(0, hex.Length).
                 Where(x => 0 == x % 2).
                 Select(x => Convert.ToByte(hex.Substring(x, 2), 16)).
                 ToArray();
    }

I haven’t got experience with .NET 2.0. Thanks!

Answer 1

void Main()
{
    string s = ToHexString(new byte[]{0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15});
    Console.WriteLine(s);

    foreach (byte b in ToByteArray(s))
        Console.WriteLine(b);
}

private static string ToHexString(byte[] bytes)
{
    StringBuilder sb = new StringBuilder();
    foreach (byte b in bytes)
        sb.Append(b.ToString("X2"));
    return sb.ToString();
}

private static byte[] ToByteArray(string hex)
{
    byte[] b = new byte[hex.Length/2];
    for (int i = 0; i < b.Length; i++)
    {
        b[i] = Convert.ToByte(hex.Substring(i*2,2), 16);
    }

    return b;
}