Lightweight implementation of 32 & 64 bit FNV Hash algorithms

FNVHash.cs

using System;

namespace DevHawk
{
    public class FNVHash
    {
        public const uint Prime32 = 16777619;
        public const uint Offset32 = 2166136261;
        public const ulong Prime64 = 1099511628211;
        public const ulong Offset64 = 14695981039346656037;

        public static uint Hash32(byte value, uint hash = Offset32) => (hash * Prime32) ^ value;

        public static uint Hash32(Span<byte> span, uint hash = Offset32)
        {
            for (var i = 0; i < span.Length; i++)
            {
                hash = Hash32(span[i], hash);
            }

            return hash;
        }

        public static uint Hash32Alt(byte value, uint hash = Offset32) => hash = (hash ^ value) * Prime32;

        public static uint Hash32Alt(Span<byte> span, uint hash = Offset32)
        {
            for (var i = 0; i < span.Length; i++)
            {
                hash = Hash32Alt(span[i], hash);
            }

            return hash;
        }

        public static ulong Hash64(byte value, ulong hash = Offset64) => (hash * Prime64) ^ value;

        public static ulong Hash64(Span<byte> span, ulong hash = Offset64)
        {
            for (var i = 0; i < span.Length; i++)
            {
                hash = Hash64(span[i], hash);
            }

            return hash;
        }

        public static ulong Hash64Alt(byte value, ulong hash = Offset64) => (hash ^ value) * Prime64;

        public static ulong Hash64Alt(Span<byte> span, ulong hash = Offset64)
        {
            for (var i = 0; i < span.Length; i++)
            {
                hash = Hash64Alt(span[i], hash);
            }

            return hash;
        }
    }
}