Prefix search through list/dictionary using .NET StringDictionary?

Question

I was wondering if .NET offers any standard functionality for doing a prefix search through a list or a dictionary object. I came across the StringDictionary, but couldn't figure out if it can do that for me.

And if it can do a prefix search, can it also do substring search or let me search using something like a regular expression?

Thanks in advance.

Answer 1

StringDictionary is merely a hash table where the keys and values are strings. This existed before generics (when Dictionary<string, string> was not possible).

The data structure that you want here is a trie. There are implementations on CodeProject:

1. Phone Directory Implementation Using TRIE
2. A Reusable Prefix Tree using Generics in C# 2.0

Or, if you're that kind of guy, roll your own (see CLRS).