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TaskScheduler.TryExecuteTaskInline(Task, Boolean) Method

Definition

Determines whether the provided Task can be executed synchronously in this call, and if it can, executes it.

protected:
 abstract bool TryExecuteTaskInline(System::Threading::Tasks::Task ^ task, bool taskWasPreviouslyQueued);
[System.Security.SecurityCritical]
protected abstract bool TryExecuteTaskInline (System.Threading.Tasks.Task task, bool taskWasPreviouslyQueued);
protected abstract bool TryExecuteTaskInline (System.Threading.Tasks.Task task, bool taskWasPreviouslyQueued);
[<System.Security.SecurityCritical>]
abstract member TryExecuteTaskInline : System.Threading.Tasks.Task * bool -> bool
abstract member TryExecuteTaskInline : System.Threading.Tasks.Task * bool -> bool
Protected MustOverride Function TryExecuteTaskInline (task As Task, taskWasPreviouslyQueued As Boolean) As Boolean

Parameters

task
Task

The Task to be executed.

taskWasPreviouslyQueued
Boolean

A Boolean denoting whether or not task has previously been queued. If this parameter is True, then the task may have been previously queued (scheduled); if False, then the task is known not to have been queued, and this call is being made in order to execute the task inline without queuing it.

Returns

A Boolean value indicating whether the task was executed inline.

Attributes

Exceptions

The task argument is null.

The task was already executed.

Remarks

A class derived from TaskScheduler implements this function to support inline execution of a task on a thread that initiates a wait on that task object. Inline execution is optional, and the request may be rejected by returning false. However, the more tasks that can be inlined, the better the scheduler will scale. In fact, a scheduler that inlines too little may be prone to deadlocks. A proper implementation should ensure that a request executing under the policies guaranteed by the scheduler can successfully inline. For example, if a scheduler uses a dedicated thread to execute tasks, any inlining requests from that thread should succeed.

If a scheduler decides to perform the inline execution, it should do so by calling to the base TaskScheduler's TryExecuteTask method with the provided task object, propagating the return value. It may also be appropriate for the scheduler to remove an inlined task from its internal data structures if it decides to honor the inlining request. Note, however, that under some circumstances a scheduler may be asked to inline a task that was not previously provided to it with the QueueTask method.

The derived scheduler is responsible for making sure that the calling thread is suitable for executing the given task as far as its own scheduling and execution policies are concerned.

For more information, see TaskScheduler.

Applies to

See also