Saturday, January 19, 2008

static class ObjectExtension
   {
       public static object Evil(this object target
           , string s)
       {
           return target.Evil(s, '.', '\\', '/', ',');
       }
       public static object Evil(this object target
           , string s, params  
           char[] separator)
       {
           var array = s.Split(separator,
               StringSplitOptions.RemoveEmptyEntries);
           if (array.Length == 0)
               return target;
           var members = target.GetType().GetMember
               (array.First().Trim());
           if (members.Length == 0)
               return null;
           var ret = members.First().GetValue(target);
           if (array.Length > 1)//recurse
               return ret.Evil(string.Join(".", array.Skip
                   (1).ToArray()));
           return ret;
       }
       static object GetValue(this MemberInfo target, 
           object obj)
       {
           switch (target.MemberType)
           {
               case MemberTypes.Property:
                   return ((PropertyInfo)target).GetValue
                       (obj, null);
               case MemberTypes.Field:
                   return ((FieldInfo)target).GetValue
                       (obj);
               case MemberTypes.Method:
                   return ((MethodInfo)target).Invoke
                       (obj, null);
           }
           return null;
       }
   }

using System;
using System.Linq;
using System.Reflection;
namespace EvilObjectExtension
{
    public class Address
    {
        public string Street;
        public string Postcode { get; set; }
        public int HouseNumber;
    }
    public class Person
    {
        public int Age { get; set; }
        public string Name { get; set; }
        public Address Home;
    }
    class Program
    {
        static void Main(string[] args)
        {
            var person = new Person
            {
                Age = 893,
                Home = new Address
                {
                    HouseNumber = 10,
                    Street = "High Road",
                    Postcode = "SW13 3AD"
                }
                ,
                Name = "Rupert"
            };
            Console.WriteLine("Name: {0}", person.Evil("Name"));
            Console.WriteLine("Age: {0}", person.Evil("Age"));
            Console.WriteLine("Postcode: {0}", person.Evil
                ("Home.Postcode"));
            //"Now.Now.Now.DayOfWeek.ToString" works because 
            //Type.GetMember searches the current type and its 
            //base types, and DateTime.Now is itself DateTime.
            Console.WriteLine(DateTime.Now.Evil
                ("Now.Now.Now.DayOfWeek.ToString"));
            //extra delimiters work
            var type = person.Evil(".Home.GetType./");
            Console.ReadKey();
        }
    }
    static class ObjectExtension
    {
        public static object Evil(this object target
            , string s)
        {
            return target.Evil(s, '.', '\\', '/', ',');
        }
        public static object Evil(this object target
            , string s, params  
            char[] separator)
        {
            var array = s.Split(separator,
                StringSplitOptions.RemoveEmptyEntries);
            if (array.Length == 0)
                return target;
            var members = target.GetType().GetMember
                (array.First().Trim());
            if (members.Length == 0)
                return null;
            var ret = members.First().GetValue(target);
            if (array.Length > 1)//recurse
                return ret.Evil(string.Join(".", array.Skip
                    (1).ToArray()));
            return ret;
        }
        static object GetValue(this MemberInfo target, 
            object obj)
        {
            switch (target.MemberType)
            {
                case MemberTypes.Property:
                    return ((PropertyInfo)target).GetValue
                        (obj, null);
                case MemberTypes.Field:
                    return ((FieldInfo)target).GetValue
                        (obj);
                case MemberTypes.Method:
                    return ((MethodInfo)target).Invoke
                        (obj, null);
            }
            return null;
        }
    }
}