MD5 Hash

To generate an MD5 like 9adff06850bedeace9d0c6ebfe7ce507

private byte[] GetData(string filePath, string fileName, out string md5)
{
    string path = Path.Combine(filePath, fileName);

    byte[] bytes = System.IO.File.ReadAllBytes(path);

    md5 = GetHash(bytes);

    return bytes;
}

private string GetHash(byte[] data)
{
    byte[] bytes = System.Security.Cryptography.MD5.Create().ComputeHash(data);

    return StringifyMD5(bytes); // This method will return something like 9adff06850bedeace9d0c6ebfe7ce507
}

private string StringifyMD5(IEnumerable< byte> bytes)
{
    var result = new StringBuilder();

    foreach (byte b in bytes)
    {
        result.AppendFormat("{0:x2}", b);
    }

    return result.ToString();
}

we can also use it to generate a hash based on a string, for example, a filename:

string fileName = "some_file_name.xml";
string hash = GetHash(System.Text.Encoding.UTF8.GetBytes(fileName));