Enum HasAny() Extension (C# >= 9) Highly optimized

EnumExtensions.cs

using System;

public static class EnumExtensions
{
	/// <summary> Checks if enum 'a' contains any of the value(s) from 'b' </summary>
	public static bool HasAny<EnumType>(this EnumType a, EnumType b)
		where EnumType : Enum
	{
		// Check for the supported enum types
		return a.GetTypeCode() switch
		{
			// byte
			TypeCode.Byte => HasAny(a, (byte)(object)b),
			// sbyte
			TypeCode.SByte => HasAny(a, (sbyte)(object)b),
			// short
			TypeCode.Int16 => HasAny(a, (short)(object)b),
			// ushort
			TypeCode.UInt16 => HasAny(a, (ushort)(object)b),
			// int
			TypeCode.Int32 => HasAny(a, (int)(object)b),
			// uint
			TypeCode.UInt32 => HasAny(a, (uint)(object)b),
			// long
			TypeCode.Int64 => HasAny(a, (long)(object)b),
			// ulong
			TypeCode.UInt64 => HasAny(a, (ulong)(object)b),
			_ => throw new NotSupportedException("Unknown Error. This shouldn't be happened!"),
		};
	}

	/// <summary> Checks if enum 'a' contains any of the value(s) from 'b' </summary>
	public static bool HasAny<EnumType>(this EnumType a, byte b)
		where EnumType : Enum
	{
		EnumUtils.ValidateFlagEnum<EnumType>();
		EnumUtils.ValidateUnderlyingType<EnumType, byte>();
		return ((byte)(object)a & b) != 0;
	}

	/// <summary> Checks if enum 'a' contains any of the value(s) from 'b' </summary>
	public static bool HasAny<EnumType>(this EnumType a, sbyte b)
		where EnumType : Enum
	{
		EnumUtils.ValidateFlagEnum<EnumType>();
		EnumUtils.ValidateUnderlyingType<EnumType, sbyte>();
		return ((sbyte)(object)a & b) != 0;
	}

	/// <summary> Checks if enum 'a' contains any of the value(s) from 'b' </summary>
	public static bool HasAny<EnumType>(this EnumType a, short b)
		where EnumType : Enum
	{
		EnumUtils.ValidateFlagEnum<EnumType>();
		EnumUtils.ValidateUnderlyingType<EnumType, short>();
		return ((short)(object)a & b) != 0;
	}

	/// <summary> Checks if enum 'a' contains any of the value(s) from 'b' </summary>
	public static bool HasAny<EnumType>(this EnumType a, ushort b)
		where EnumType : Enum
	{
		EnumUtils.ValidateFlagEnum<EnumType>();
		EnumUtils.ValidateUnderlyingType<EnumType, ushort>();
		return ((ushort)(object)a & b) != 0;
	}

	/// <summary> Checks if enum 'a' contains any of the value(s) from 'b' </summary>
	public static bool HasAny<EnumType>(this EnumType a, int b)
		where EnumType : Enum
	{
		EnumUtils.ValidateFlagEnum<EnumType>();
		EnumUtils.ValidateUnderlyingType<EnumType, int>();
		return ((int)(object)a & b) != 0;
	}

	/// <summary> Checks if enum 'a' contains any of the value(s) from 'b' </summary>
	public static bool HasAny<EnumType>(this EnumType a, uint b)
		where EnumType : Enum
	{
		EnumUtils.ValidateFlagEnum<EnumType>();
		EnumUtils.ValidateUnderlyingType<EnumType, uint>();
		return ((uint)(object)a & b) != 0;
	}

	/// <summary> Checks if enum 'a' contains any of the value(s) from 'b' </summary>
	public static bool HasAny<EnumType>(this EnumType a, long b)
		where EnumType : Enum
	{
		EnumUtils.ValidateFlagEnum<EnumType>();
		EnumUtils.ValidateUnderlyingType<EnumType, long>();
		return ((long)(object)a & b) != 0;
	}

	/// <summary> Checks if enum 'a' contains any of the value(s) from 'b' </summary>
	public static bool HasAny<EnumType>(this EnumType a, ulong b)
		where EnumType : Enum
	{
		EnumUtils.ValidateFlagEnum<EnumType>();
		EnumUtils.ValidateUnderlyingType<EnumType, ulong>();
		return ((ulong)(object)a & b) != 0;
	}
}

EnumUtils.cs

using System;

public static class EnumUtils
{
	/// <summary> Throws exception on mismatch </summary>
	public static void ValidateUnderlyingType<EnumType, EnumUnderlyingType>()
		where EnumType : Enum
		where EnumUnderlyingType : struct
	{
		if (Enum.GetUnderlyingType(typeof(EnumType)) != typeof(EnumUnderlyingType))
			throw new NotSupportedException("Underlying value Type of EnumType and EnumUnderlyingType must be same and enums only support; byte, sbyte, short, ushort, int, uint, long, or ulong");
	}

	public static void ValidateFlagEnum<T>()
		where T : Enum
	{
		if (!typeof(T).IsDefined(typeof(FlagsAttribute), inherit: false))
			throw new NotSupportedException("Only flag enums with Flags attribute supported");
	}
}