You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
54 lines
2.1 KiB
54 lines
2.1 KiB
#if NET20 || NET30 || NET35 || !NET_4_6 |
|
|
|
using System.Diagnostics.Contracts; |
|
|
|
namespace System.Threading.Tasks |
|
{ |
|
internal sealed class ContinuationTaskFromResultTask<TAntecedentResult> : Task, IContinuationTask |
|
{ |
|
private Task<TAntecedentResult> _antecedent; |
|
|
|
public ContinuationTaskFromResultTask(Task<TAntecedentResult> antecedent, Delegate action, object state, TaskCreationOptions creationOptions, InternalTaskOptions internalOptions) |
|
: base(action, state, InternalCurrentIfAttached(creationOptions), default(CancellationToken), creationOptions, internalOptions, TaskScheduler.Default) |
|
{ |
|
Contract.Requires(action is Action<Task<TAntecedentResult>> || action is Action<Task<TAntecedentResult>, object>, "Invalid delegate type in ContinuationTaskFromResultTask"); |
|
_antecedent = antecedent; |
|
CapturedContext = ExecutionContext.Capture(); |
|
} |
|
|
|
public Task Antecedent |
|
{ |
|
get { return _antecedent; } |
|
} |
|
|
|
/// <summary> |
|
/// Evaluates the value selector of the Task which is passed in as an object and stores the result. |
|
/// </summary> |
|
internal override void InnerInvoke() |
|
{ |
|
// Get and null out the antecedent. This is crucial to avoid a memory |
|
// leak with long chains of continuations. |
|
var antecedent = _antecedent; |
|
Contract.Assert(antecedent != null, "No antecedent was set for the ContinuationTaskFromResultTask."); |
|
_antecedent = null; |
|
|
|
// Invoke the delegate |
|
Contract.Assert(Action != null); |
|
var action = Action as Action<Task<TAntecedentResult>>; |
|
if (action != null) |
|
{ |
|
action(antecedent); |
|
return; |
|
} |
|
var actionWithState = Action as Action<Task<TAntecedentResult>, object>; |
|
if (actionWithState != null) |
|
{ |
|
actionWithState(antecedent, State); |
|
return; |
|
} |
|
Contract.Assert(false, "Invalid Action in ContinuationTaskFromResultTask"); |
|
} |
|
} |
|
} |
|
|
|
#endif |