General Performance Tip: Hashing Data

When hashing a byte array or a stream, developers typically code it as follows:

using (var sha256 = SHA256.Create())
{
    var digest = sha256.ComputeHash(byteArray);
}

Hashing the same data can be achieved using the HashData() method, as demonstrated in the following example:

var digest = SHA256.HashData(byteArray);

Not only does this require less code, but there is also no need to worry about disposing of the SHA256 object.

Finally, consider employing TryHashData() as demonstrated in the following example:

var hash = new byte[byteArray.Length];
var digest = SHA256.TryHashData(byteArray, hash, out var _);

Benchmark Results

The results clearly indicate that employing HashData() is 1.03 times faster than utilizing ComputeHash() and 1.34 times faster than TryHashData(). Additionally, it requires fewer memory allocations.

Allocations: HashData(): 56 bytes, ComputeHash(): 240 bytes, TryHashData(): 2,072 bytes.

This is how I have it setup checking for this issue in my EditorConfig: dotnet_diagnostic.CA1850.severity = error

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