Slicing a FormCollection by keys that start with a certain string

Question

Is there a nice linqy way of splitting a FormCollection into a Dictionary that contains only those keys that start wi

Answer 1

[HttpPost]
public ActionResult Index(FormCollection collection)
{
     Dictionary<string,object> form = new Dictionary<string, object>();
     collection.CopyTo(form);
     return View();
}

Answer 2

If you're looking for a "nice" way of taking an existing dictionary, producing a new dictionary with copies of keys+values, for a subset of the keys, some LINQ code will do this nicely:

var appSettings = formCollection.AllKeys
    .Where(k => k.StartsWith("AppSettings."))
    .ToDictionary(k => k, k => formCollection[k]);