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CoreTaskExtensionsSelectTSource, TResult Method (TaskTSource, FuncTaskTSource, TResult, Boolean)
Synchronously execute a continuation when a task completes. The supportsErrors parameter specifies whether the continuation is executed if the antecedent task is faulted.

Namespace: Rackspace.Threading
Assembly: Rackspace.Threading (in Rackspace.Threading.dll) Version: 2.1.0-beta1
Syntax
public static Task<TResult> Select<TSource, TResult>(
	this Task<TSource> task,
	Func<Task<TSource>, TResult> continuationFunction,
	bool supportsErrors
)

Parameters

task
Type: System.Threading.TasksTaskTSource
The antecedent task.
continuationFunction
Type: SystemFuncTaskTSource, TResult
The continuation function to execute when task completes.
supportsErrors
Type: SystemBoolean
if the continuationFunction properly handles a faulted antecedent task; otherwise, .

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: TaskTResult
A 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
ExceptionCondition
ArgumentNullException

If task is .

-or-

If continuationFunction is .

Remarks

This code implements support for the following construct without requiring the use of /.

C#
try
{
    TSource source = await task.ConfigureAwait(false);
}
catch
{
    if (!supportsErrors)
        throw;
}

return continuationFunction(task);

If the antecedent task is canceled, or faulted with supportsErrors set to , 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

Threading Library

Supported in: 2.1, 2.0, 1.1, 1.0
See Also