Flag enums extension methods for Unity (if using .NET 3.5 or less)

EnumExtension.cs

/// Created by @cortvi
/// adapted code from:
/// https://stackoverflow.com/questions/28167873/custom-generic-setflag-unsetflag-extension-methods
using System;
using System.Globalization;

public static class Extension
{
	/// <summary>
	/// Usage: "if ( someEnum.HasFlag (someEnumFlag) ) {..}"
	/// </summary>
	public static bool HasFlag<T> ( this T e, T flag ) where T : struct, IConvertible
	{
		var value = e.ToInt32(CultureInfo.InvariantCulture);
		var target = flag.ToInt32(CultureInfo.InvariantCulture);

		return ((value & target) == target);
	}

	/// <summary>
	/// Usage: "someEnum = someEnum.SetFlag (someEnumFlag);"
	/// </summary>
	public static T SetFlag<T> (this T e, T flag) where T : struct, IConvertible
	{
		var value = e.ToInt32(CultureInfo.InvariantCulture);
		var newFlag = flag.ToInt32(CultureInfo.InvariantCulture);

		return (T)(object)(value | newFlag);
	}

	/// <summary>
	/// Usage: "someEnum = someEnum.UnsetFlag (someEnumFlag);"
	/// </summary>
	public static T UnsetFlag<T> (this T en, T flag) where T : struct, IConvertible
	{
		int value = en.ToInt32(CultureInfo.InvariantCulture);
		int newFlag = flag.ToInt32(CultureInfo.InvariantCulture);

		return (T)(object)(value & ~newFlag);
	}
}