Initializes a new instance of the HMACSHA256 class with a randomly generated key.
Assembly: mscorlib (in mscorlib.dll)
HMACSHA256 is a type of keyed hash algorithm that is constructed from the SHA-256 hash function and used as a Hash-based Message Authentication Code (HMAC). The HMAC process mixes a secret key with the message data, hashes the result with the hash function, mixes that hash value with the secret key again, and then applies the hash function a second time. The output hash is 256 bits in length.
This constructor uses a 64-byte, randomly generated key.