using System;
using System.Reflection;

public class Test
{
	public static void Main()
	{
		var res = typeof(Books).GetField("IndianInTheCupboard").GetCustomAttribute<BookDetails>(false).Author;
		Console.WriteLine(res);
	}
}

[AttributeUsage(AttributeTargets.Field)]
public class BookDetails : Attribute
{
    public string Author { get; }
    public int YearPublished { get; }

    public BookDetails(string author, int yearPublished)
    {
        Author = author;
        YearPublished = yearPublished;
    }
}

public enum Books
{
    [BookDetails("Jack London", 1906)]
    WhiteFange,

    [BookDetails("Herman Melville", 1851)]
    MobyDick,

    [BookDetails("Lynne Reid Banks", 1980)]
    IndianInTheCupboard

}