I have a big dictionary where the key is decimal, but the GetHashCode() of System.Decimal is disasterously bad. To prove my guess, I ran a for loop with 100.000 neigboring d
public static class Utils
{
[StructLayout(LayoutKind.Explicit)]
struct DecimalGuidConverter
{
[FieldOffset(0)]
public decimal Decimal;
[FieldOffset(0)]
public Guid Guid;
}
private static DecimalGuidConverter _converter;
public static Guid DecimalToGuid(decimal dec)
{
_converter.Decimal = dec;
return _converter.Guid;
}
public static decimal GuidToDecimal(Guid guid)
{
_converter.Guid = guid;
return _converter.Decimal;
}
}
// Prints 000e0000-0000-0000-8324-6ae7b91d0100
Console.WriteLine(Utils.DecimalToGuid((decimal) Math.PI));
// Prints 00000000-0000-0000-1821-000000000000
Console.WriteLine(Utils.DecimalToGuid(8472m));
// Prints 8472
Console.WriteLine(Utils.GuidToDecimal(Guid.Parse("00000000-0000-0000-1821-000000000000")));