How can I create a dynamic proxy out of a List<T>

Question

I'm using Castle Dynamic Proxy CreateClassProxyWithTarget using an already existing list. Basically, I'd like to to intercept the calls being made to the list indexer.

I've tried a bunch of combination to achieve this goal but each time the created proxy returns an empty list.

For example :

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Castle.DynamicProxy;

namespace DP
{
    class Program
    {
        private static readonly ProxyGenerator _generator = new ProxyGenerator(new PersistentProxyBuilder());

        static void Main(string[] args)
        {
            ListString ls = new ListString();
            ls.Add("hello");

            List<string> ls2 = (ListString)_generator.CreateClassProxyWithTarget(typeof(ListString), ls, new Interceptor());

            var x = ls2[0];
        }
    }

    public class ListString : List<String>
    {
        public ListString() : base() { }
        public ListString(IEnumerable<String> strings) : base(strings) { }
    }
}

Please help! It's driving me mad ! I tried Castle 3.2 and 2.5, none of them seem to work. I can achieve good result with "normal" objects.

Answer 1

Indexer on List<T> is not virtual and cannot be intercepted by DynamicProxy.

You can proxy IList<T> instead.