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BackgroundTaskDeferral Class

Definition

Represents a background task deferral returned by the IBackgroundTaskInstance.GetDeferral method.

public ref class BackgroundTaskDeferral sealed
/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Standard)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.MTA)]
class BackgroundTaskDeferral final
/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.MTA)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
class BackgroundTaskDeferral final
[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Standard)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.MTA)]
public sealed class BackgroundTaskDeferral
[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.MTA)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
public sealed class BackgroundTaskDeferral
Public NotInheritable Class BackgroundTaskDeferral
Inheritance
Object Platform::Object IInspectable BackgroundTaskDeferral
Attributes

Windows requirements

Device family
Windows 10 (introduced in 10.0.10240.0)
API contract
Windows.Foundation.UniversalApiContract (introduced in v1.0)

Examples

The following example shows how to use a background task deferral to delay a task from closing prematurely while asynchronous code is still running. Ensure that you complete all background task deferrals. Most background tasks have a timeout after which the app will be suspended or terminated regardless of whether there are any pending deferrals. However, leaving outstanding background task deferrals interferes with the system's ability to manage process lifetimes in a timely way.

//
// Declare that your background task's Run method makes asynchronous calls by
// using the async keyword.
//
public async void Run(IBackgroundTaskInstance taskInstance)
{
    //
    // Create the deferral by requesting it from the task instance.
    //
    BackgroundTaskDeferral deferral = taskInstance.GetDeferral();

    //
    // Call asynchronous method(s) using the await keyword.
    //
    var result = await ExampleMethodAsync();

    //
    // Once the asynchronous method(s) are done, close the deferral.
    //
    deferral.Complete();
}

Methods

Complete()

Informs the system that an asynchronous operation associated with a background task has finished.

Applies to