System.Security.Cryptography.RSACryptoServiceProvider.SignHash C# (CSharp) Method

        public override byte[] SignHash(
            byte[] hash,
            HashAlgorithmName hashAlgorithm,
            RSASignaturePadding padding)
        {
            if (hash == null)
                throw new ArgumentNullException(nameof(hash));
            if (string.IsNullOrEmpty(hashAlgorithm.Name))
                throw HashAlgorithmNameNullOrEmpty();
            if (padding == null)
                throw new ArgumentNullException(nameof(padding));
            if (padding != RSASignaturePadding.Pkcs1)
                throw PaddingModeNotSupported();

            return SignHash(hash, GetAlgorithmId(hashAlgorithm));
        }

        /// <summary>
        /// Creates a base64 encoded signature for the SHA-256 hash of the specified data.
        /// </summary>
        /// <param name="data">The data to hash and sign. Must not be null.</param>
        /// <returns>The base-64 encoded signature.</returns>
        public string CreateSignature(byte[] data)
        {
            data.ThrowIfNull(nameof(data));

            using (var hashAlg = SHA256.Create())
            {
                byte[] assertionHash = hashAlg.ComputeHash(data);
#if NETSTANDARD
                var sigBytes = key.SignHash(assertionHash, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1);
#else
                var sigBytes = key.SignHash(assertionHash, Sha256Oid);
#endif
                return(Convert.ToBase64String(sigBytes));
            }
        }