IAsyncServiceProvider3.GetServiceAsync<TService,TInterface> Method
Definition
Important
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Retrieves a proffered service asynchronously, specifying whether to throw an exception if it could not be retrieved.
public System.Threading.Tasks.Task<TInterface?> GetServiceAsync<TService,TInterface> (bool throwOnFailure, System.Threading.CancellationToken cancellationToken) where TInterface : class;abstract member GetServiceAsync : bool * System.Threading.CancellationToken -> System.Threading.Tasks.Task<'Interface (requires 'Interface : null)> (requires 'Interface : null)Public Function GetServiceAsync(Of TService, TInterface) (throwOnFailure As Boolean, cancellationToken As CancellationToken) As Task(Of TInterface)Type Parameters
- TService
The service identity of the proffered service to retrieve.
- TInterface
The interface used to interact with the proffered service. If TService is not registered as async or free-threaded, then this cast will be performed on the main thread.
Parameters
- throwOnFailure
- Boolean
true to throw an exception if the service could not be retrieved; otherwise, false to return null on failure.
- cancellationToken
- CancellationToken
A token whose cancellation indicates that the caller no longer is interested in the result. This will not cancel the in-progress loading of packages and/or creation of services as a result of the service retrieval, but this token will result in an expedient cancellation of the returned Task.
Returns
A task representing the service retrieval whose result is the service or null if there was a failure and throwOnFailure is false.
Exceptions
cancellationToken has been canceled.
throwOnFailure is true and there was a failure retrieving the service due to one of the following conditions:
- The service threw an exception during activation. InnerException may include details about the underlying failure.
- The associated package failed to load. InnerException may include details about the underlying failure.
- The associated package could not be found, or the package did not correctly proffer the service.
- The associated package proffered
null. - The service does not support the requested interface specified by
TInterface. - The environment has starting shutting down and the retrieval would have resulted in a package load.
Remarks
Prefer this method over an explicit cast to TInterface to avoid a blocking RPC call if the underlying service is STA-bound, which can hang if the UI thread is blocked in a Run(Func<Task>) or Join(CancellationToken).
Note the difference in behavior this method has around exceptions to its non-generic equivalents GetServiceAsync(Type) and GetServiceAsync(Type, Boolean).
This method is safe to access from any thread.