.NET SHA256 Vs Object.GetHashCode()
c#
Solution
You cannot compare the two as they are built for two entirely different purposes. What is your goal? - Encryption or simple object lookup?
For object lookup (in a hashtable): `GetHashCode()`
For encryption: SHA256 combined with e.g. AES.
`GetHashCode()` should be overridden for your type and ideally only use immutable fields, ie. fields not changing over the lifetime of the object, read-only fields is a good example of this ;-)
SHA256 is used for example to hash a password for usage in an encryption algorithm that takes 256-bit keys. The point of a hashing algorithm used for encryption is that it must be slow (the opposite of the object lookup scenario) to make it more difficult to bruteforce attack passwords.
So no pros/cons as such, but really depends on your goal. Use the right tool for the purpose :-)
Problem
What are the pros/cons when it comes to using SHA256 Vs Object.GetHashCode()? In the code below, the output is identical for both methods, however the GetHashCode() seems a lot simpler, requires fewer objects/code. ``` class Program { static void Main(string[] args) { TestGetHashCode(); TestSha256(); Console.Read(); } static void TestSha256() { Console.WriteLine("Testing SHA256"); UnicodeEncoding byteConverter = new UnicodeEncoding(); SHA256 sha256 = SHA256.Create(); string data = "A paragraph of text"; byte[] hashA = sha256.ComputeHash(byteConverter.GetBytes(data)); data = "A paragraph of changed text"; byte[] hashB = sha256.ComputeHash(byteConverter.GetBytes(data)); data = "A paragraph of text"; byte[] hashC = sha256.ComputeHash(byteConverter.GetBytes(data)); Console.WriteLine(hashA.SequenceEqual(hashB)); // Displays: false Console.WriteLine(hashA.SequenceEqual(hashC)); // Displays: true } static void TestGetHashCode() { Console.WriteLine("Testing Object.GetHashCode()"); string data = "A paragraph of text"; int hashA = data.GetHashCode(); data = "A paragraph of changed text"; int hashB = data.GetHashCode(); data = "A paragraph of text"; int hashC = data.GetHashCode(); Console.WriteLine(hashA.Equals(hashB)); // Displays: false Console.WriteLine(hashA.Equals(hashC)); // Displays: true } } ```