Task.RunSynchronously Method

Runs the Task synchronously on the current TaskScheduler.

Namespace:  System.Threading.Tasks
Assembly:  mscorlib (in mscorlib.dll)

member RunSynchronously : unit -> unit

ExceptionCondition
ObjectDisposedException

The Task instance has been disposed.

InvalidOperationException

The Task is not in a valid state to be started. It may have already been started, executed, or canceled, or it may have been created in a manner that doesn't support direct scheduling.

Ordinarily, tasks are executed asynchronously on a thread pool thread and do not block the calling thread. Tasks executed by calling the RunSynchronously() method are associated with the current TaskScheduler and are run on the calling thread. If the target scheduler does not support running this task on the calling thread, the task will be scheduled for execution on the scheduler, and the calling thread will block until the task has completed execution. Because of this, the calling thread does not need to call a method such as Wait to ensure that the task has completed execution.

Tasks executed by calling the RunSynchronously method are instantiated by calling a Task or Task(TResult) class constructor. The task to be run synchronously must be in the TaskStatus.Created state. A task may be started and run only once. Any attempts to schedule a task a second time results in an exception.

The following example compares a task executed by calling the RunSynchronously method with one executed asynchronously. In both cases, the tasks execute identical lambda expressions that display the task ID and the ID of the thread on which the task is running. The task calculates the sum of the integers between 1 and 1,000,000. As the output from the example shows, the task executed by calling the RunSynchronously method runs on the application thread, while the asynchronous task does not.

No code example is currently available or this language may not be supported.

.NET Framework

Supported in: 4.6, 4.5, 4

.NET Framework Client Profile

Supported in: 4

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
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