MapRedirect for temp and perm redirecting

RouteCollectionExtensions.cs

public static class RouteCollectionExtensions
{
    public static void MapRedirect(this RouteCollection rc, string url, string dest, bool perm = false)
    {
        rc.Add(new Route(url, new RedirectRouteHandler(dest, perm)));
    }
}

public class VirtualPathRouteHandlerBase
{
    private static readonly Regex Regex = new Regex(@"{(\w+)}");
    private string _virtualPath;
    private IList<string> _parsed;

    public VirtualPathRouteHandlerBase(string virtualPath)
    {
        VirtualPath = virtualPath;
    }

    public string VirtualPath
    {
        get { return _virtualPath; }
        set
        {
            _virtualPath = value;
            _parsed = SplitUrlToPathSegmentStrings(value);
        }
    }

    public string BuildVirtualPath(RequestContext requestContext)
    {
        var sb = new StringBuilder();
        foreach (string list in _parsed)
            sb.Append(Regex.Replace(list, a =>
            {
                object v;
                if (requestContext.RouteData.Values.TryGetValue(a.Groups[1].Value, out v))
                    return v + "";
                throw new Exception(string.Format("{0} not found in request context", a.Value));
            }));
        return sb.ToString();
    }

    internal static IList<string> SplitUrlToPathSegmentStrings(string url)
    {
        var list = new List<string>();
        if (!string.IsNullOrEmpty(url))
        {
            int index;
            for (int i = 0; i < url.Length; i = index + 1)
            {
                index = url.IndexOf('/', i);
                if (index == -1)
                {
                    string str = url.Substring(i);
                    if (str.Length > 0)
                        list.Add(str);
                    return list;
                }
                string item = url.Substring(i, index - i);
                if (item.Length > 0)
                {
                    list.Add(item);
                }
                list.Add("/");
            }
        }
        return list;
    }
}

public class RedirectRouteHandler : VirtualPathRouteHandlerBase, IRouteHandler
{
    private readonly bool _perm;

    public RedirectRouteHandler(string virtualPath, bool perm)
        : base(virtualPath)
    {
        _perm = perm;
    }

    public IHttpHandler GetHttpHandler(RequestContext requestContext)
    {
        return new RedirectHttpHandler(BuildVirtualPath(requestContext), _perm);
    }
}

public class RedirectHttpHandler : IHttpHandler
{
    private readonly string _virtualPath;
    private readonly bool _perm;

    public RedirectHttpHandler(string virtualPath, bool perm)
    {
        _virtualPath = virtualPath;
        _perm = perm;
    }

    public void ProcessRequest(HttpContext context)
    {
        context.Response.Redirect(_virtualPath, !_perm);
        context.Response.StatusCode = 301;
        context.Response.End();
    }

    public bool IsReusable
    {
        get { return false; }
    }
}