using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(MissionStateEnum.Assigned.IsAtLeastStarted());

        MissionStateEnum state = MissionStateEnum.Started;

        if (state.IsAtLeastStarted())

        {

            state.Dump();

        }

    }

}

​

[AttributeUsage(AttributeTargets.Field, AllowMultiple = false)]

class AtLeastStartedAttribute : Attribute {}

​

public enum MissionStateEnum

{

    Pending = 1,

    Assigned = 2,

    [AtLeastStarted]

    Started = 3,

    [AtLeastStarted]

    Done = 4,

    [AtLeastStarted]

    Canceled = 5

}

​

public static class MissionStateEnumExtension

{

    public static bool IsAtLeastStarted(this MissionStateEnum stateEnum)

    {

        var name = Enum.GetName(typeof(MissionStateEnum), stateEnum);

        return typeof(MissionStateEnum).GetField(name)

            .GetCustomAttributes(typeof(AtLeastStartedAttribute), false)

            .Any();

    }

}

​