How to get all route-values after {controller}/{method}

Question

I do render buttons in order to change the language as following:

                    <%: Html.ActionLink(
                        "EN", 
                        ViewContext.RouteData.Values["action"].ToString(), 
                        new { lang = "en" }, new { @class="tab" })%>

This would render me the link as follows: {...}\en\MyController\MyMethod - the only problem left is that I lose all routing values, which follow after the method's name. How is it possible to add them as well?

Thanks for any tips!

Answer 1

I actually use a few handy extension methods:

    public static RouteValueDictionary ToRouteValueDictionary(this NameValueCollection collection)
    {
        RouteValueDictionary dic = new RouteValueDictionary();
        foreach (string key in collection.Keys)
            dic.Add(key, collection[key]);

        return dic;
    }

    public static RouteValueDictionary AddOrUpdate(this RouteValueDictionary dictionary, string key, object value)
    {
        dictionary[key] = value;
        return dictionary;
    }

    public static RouteValueDictionary RemoveKeys(this RouteValueDictionary dictionary, params string[] keys)
    {
        foreach (string key in keys)
            dictionary.Remove(key);

        return dictionary;
    }

This allows me to do the following:

//Update the current routevalues and pass it as the values.
@Html.ActionLink("EN", ViewContext.RouteData.Values["action"], ViewContext.RouteData.Values.AddOrUpdate("lang", "en"))

//Grab the querystring, update a value, and set it as routevalues.
@Html.ActionLink("EN", ViewContext.RouteData.Values["action"], Request.QueryString.ToRouteValueDictionary.AddOrUpdate("lang", "en"))