CoreTaskExtensionsSelectTSource, TResult Method (TaskTSource, FuncTaskTSource, TResult) |
Synchronously execute a continuation when a task completes successfully.
Namespace: Rackspace.ThreadingAssembly: Rackspace.Threading (in Rackspace.Threading.dll) Version: 1.1.0.0
Syntax
public static Task<TResult> Select<TSource, TResult>(
this Task<TSource> task,
Func<Task<TSource>, TResult> continuationFunction
)
<ExtensionAttribute>
Public Shared Function Select(Of TSource, TResult) (
task As Task(Of TSource),
continuationFunction As Func(Of Task(Of TSource), TResult)
) As Task(Of TResult)
public:
[ExtensionAttribute]
generic<typename TSource, typename TResult>
static Task<TResult>^ Select(
Task<TSource>^ task,
Func<Task<TSource>^, TResult>^ continuationFunction
)
[<ExtensionAttribute>]
static member Select :
task : Task<'TSource> *
continuationFunction : Func<Task<'TSource>, 'TResult> -> Task<'TResult>
Parameters
- task
- Type: System.Threading.TasksTaskTSource
The antecedent task. - continuationFunction
- Type: SystemFuncTaskTSource, TResult
The continuation function to execute when task completes successfully.
Type Parameters
- TSource
- The type of the result produced by the antecedent TaskTResult.
- TResult
- The type of the result produced by the continuation TaskTResult.
Return Value
Type:
TaskTResultA
Task representing the asynchronous operation. When the task completes successfully,
the
Result property will contain the result returned from the
continuationFunction.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type
TaskTSource. When you use instance method syntax to call this method, omit the first parameter. For more information, see
Extension Methods (Visual Basic) or
Extension Methods (C# Programming Guide).
Exceptions
Remarks
This code implements support for the following construct without requiring the use of
/
.
TSource source = await task.ConfigureAwait(false);
return continuationFunction(task);
If the antecedent task is canceled or faulted, the status of the antecedent is
directly applied to the task returned by this method; it is not wrapped in an additional
AggregateException.
Version Information
.NET for Windows Store apps
Supported in: Windows 8
.NET Framework
Supported in: 4.5, 4.0, 3.5
Portable Class Library
Supported in: Portable Class Library (Legacy), Portable Class Library
Rackspace Threading Library
Supported in: 1.1, 1.0
See Also