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Originally published at Internet.comPart of .NET's security framework is cryptographic support, and the System.Security.Cryptography namespace is the library that supports cryptographic operations. This namespace supports encryption, digital signatures, random number generations, hashing, and secure encoding and decoding. It implements these operations using common cryptographic algorithms, namely RSA, DSA, Rijandel, Triple DES, RC2, MD5, and the SHA family (SHA1, 256, 384, and 512).
Tom Gutschmidt
One class within System.Security.Cryptography, CryptoStream, is provided to encrypt or decrypt content as it is streamed out into a file. Cryptostream defines a stream that links data to cryptographic transformations. Microsoft provides full code versions for implementing CryptoStream within C# or Visual Basic. Following their examples, encrypting a file using CryptoStream is straightforward.
First the System.Security.Cryptography needs to be included, and then a key for encryption or decryption needs to be created or declared. The key must be a constant, and contained within a class or module. There are also other restrictions based on which algorithm is being used...
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