TaskAwaiter_T.cs
Go to the documentation of this file.
1 //
2 // TaskAwaiter_T.cs
3 //
4 // Authors:
5 // Marek Safar <marek.safar@gmail.com>
6 //
7 // Copyright (C) 2011 Novell, Inc (http://www.novell.com)
8 // Copyright (C) 2011 Xamarin, Inc (http://www.xamarin.com)
9 //
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:
17 //
18 // The above copyright notice and this permission notice shall be
19 // included in all copies or substantial portions of the Software.
20 //
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.
28 //
29 
30 #if NET_4_5
31 
32 using System.Threading.Tasks;
33 
34 namespace System.Runtime.CompilerServices
35 {
36  public struct TaskAwaiter<TResult> : ICriticalNotifyCompletion
37  {
38  readonly Task<TResult> task;
39 
40  internal TaskAwaiter (Task<TResult> task)
41  {
42  this.task = task;
43  }
44 
45  public bool IsCompleted {
46  get {
47  return task.IsCompleted;
48  }
49  }
50 
51  public TResult GetResult ()
52  {
53  if (task.Status != TaskStatus.RanToCompletion)
54  throw TaskAwaiter.HandleUnexpectedTaskResult (task);
55 
56  return task.Result;
57  }
58 
59  public void OnCompleted (Action continuation)
60  {
61  if (continuation == null)
62  throw new ArgumentNullException ("continuation");
63 
64  TaskAwaiter.HandleOnCompleted (task, continuation, true, true);
65  }
66 
67  public void UnsafeOnCompleted (Action continuation)
68  {
69  if (continuation == null)
70  throw new ArgumentNullException ("continuation");
71 
72  TaskAwaiter.HandleOnCompleted (task, continuation, true, false);
73  }
74  }
75 }
76 
77 #endif
void UnsafeOnCompleted(Action continuation)