c# 计算文件 md5

static string (string filename)
{
    using (var md5 = System.Security.Cryptography.MD5.Create())
    {
        using (var stream = File.OpenRead(filename))
        {
            var hash = md5.ComputeHash(stream);
            return BitConverter.ToString(hash).Replace("-", "").ToLowerInvariant();
        }
    }
}

static bool VerifyMd5Hash(string filename, string hash)
{
    // Hash the input.
    string hashOfInput = CalculateMd5(filename);

    // Create a StringComparer an compare the hashes.
    StringComparer comparer = StringComparer.OrdinalIgnoreCase;

    if (0 == comparer.Compare(hashOfInput, hash))
    {
        return true;
    }
    else
    {
        return false;
    }
}