2 // SortSequenceContext.cs
5 // Jb Evain (jbevain@novell.com)
7 // (C) 2008 Novell, Inc. (http://www.novell.com)
9 // Permission is hereby granted, free of charge, to any person obtaining
10 // a copy of this software and associated documentation files (the
11 // "Software"), to deal in the Software without restriction, including
12 // without limitation the rights to use, copy, modify, merge, publish,
13 // distribute, sublicense, and/or sell copies of the Software, and to
14 // permit persons to whom the Software is furnished to do so, subject to
15 // the following conditions:
17 // The above copyright notice and this permission notice shall be
18 // included in all copies or substantial portions of the Software.
20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
30 using System
.Collections
.Generic
;
32 namespace System
.Linq
{
34 class SortSequenceContext
<TElement
, TKey
> : SortContext
<TElement
> {
36 Func
<TElement
, TKey
> selector
;
37 IComparer
<TKey
> comparer
;
41 public SortSequenceContext (Func
<TElement
, TKey
> selector
, IComparer
<TKey
> comparer
, SortDirection direction
, SortContext
<TElement
> child_context
)
42 : base (direction
, child_context
)
44 this.selector
= selector
;
45 this.comparer
= comparer
;
48 public override void Initialize (TElement
[] elements
)
50 if (child_context
!= null)
51 child_context
.Initialize (elements
);
53 keys
= new TKey
[elements
.Length
];
54 for (int i
= 0; i
< keys
.Length
; i
++)
55 keys
[i
] = selector (elements
[i
]);
58 public override int Compare (int first_index
, int second_index
)
60 int comparison
= comparer
.Compare (keys
[first_index
], keys
[second_index
]);
62 if (comparison
== 0) {
63 if (child_context
!= null)
64 return child_context
.Compare (first_index
, second_index
);
66 comparison
= direction
== SortDirection
.Descending
67 ? second_index
- first_index
68 : first_index
- second_index
;
71 return direction
== SortDirection
.Descending
? -comparison
: comparison
;