Dictionary MVC Route Handler

DictionaryRouteHandler.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.Routing;

public class DictionaryRouteHandler<TKey, TValue> : MvcRouteHandler 
{
    private readonly string _key;

    public DictionaryRouteHandler(string key)
    {
        this._key = key;
    }

    protected override IHttpHandler GetHttpHandler(RequestContext requestContext)
    {
        var dictionaryParameter = requestContext.RouteData.Values[this._key] as string;

        requestContext.RouteData.Values[this._key] = string.IsNullOrEmpty(dictionaryParameter) ? null : ParseUrlDictionary(dictionaryParameter);
        
        return base.GetHttpHandler(requestContext);
    }

    private static IDictionary<TKey, TValue> ParseUrlDictionary(string dictionaryParameter)
    {
        var dictionaryElements = Regex.Split(dictionaryParameter, @"([^/]+/[^/]+)+").Where(dp => Regex.IsMatch(dp, @"^[^/]+/[^/]+$"));

        var urlDictionary = dictionaryElements.Select(ParseElement).ToDictionary(kvpk => kvpk.Key, kvpv => kvpv.Value);

        return urlDictionary;
    }

    private static KeyValuePair<TKey, TValue> ParseElement(string element)
    {
        var elementParts = element.Split('/');

        var key = (TKey) Convert.ChangeType(elementParts[0], typeof (TKey));
        var value = (TValue) Convert.ChangeType(elementParts[1], typeof (TValue));

        return new KeyValuePair<TKey, TValue>(key, value);
    }
}