2 // Lookup<TKey, TElement>.cs
5 // Alejandro Serrano "Serras" (trupill@yahoo.es)
6 // Marek Safar <marek.safar@gmail.com>
8 // Copyright (C) 2007 Novell, Inc (http://www.novell.com)
10 // Permission is hereby granted, free of charge, to any person obtaining
11 // a copy of this software and associated documentation files (the
12 // "Software"), to deal in the Software without restriction, including
13 // without limitation the rights to use, copy, modify, merge, publish,
14 // distribute, sublicense, and/or sell copies of the Software, and to
15 // permit persons to whom the Software is furnished to do so, subject to
16 // the following conditions:
18 // The above copyright notice and this permission notice shall be
19 // included in all copies or substantial portions of the Software.
21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
32 using System.Collections;
33 using System.Collections.Generic;
35 namespace System.Linq {
37 public class Lookup<TKey, TElement> : IEnumerable<IGrouping<TKey, TElement>>, ILookup<TKey, TElement> {
39 Dictionary<TKey, IGrouping<TKey, TElement>> groups;
41 internal Lookup (Dictionary<TKey, List<TElement>> groups)
43 this.groups = new Dictionary<TKey, IGrouping<TKey, TElement>> ();
44 foreach (KeyValuePair<TKey, List<TElement>> group in groups)
45 this.groups.Add (group.Key, new Grouping<TKey, TElement> (group.Key, group.Value));
48 public IEnumerable<TResult> ApplyResultSelector<TResult> (Func<TKey, IEnumerable<TElement>, TResult> selector)
50 foreach (IGrouping<TKey, TElement> group in groups.Values)
51 yield return selector (group.Key, group);
56 get { return groups.Count; }
59 public bool Contains (TKey key)
61 return groups.ContainsKey (key);
64 public IEnumerable<TElement> this [TKey key]
66 get { return groups [key]; }
69 public IEnumerator<IGrouping<TKey, TElement>> GetEnumerator ()
71 return groups.Values.GetEnumerator ();
74 IEnumerator IEnumerable.GetEnumerator ()
76 return groups.Values.GetEnumerator ();