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IVsService<T>.GetValueOrNullAsync(CancellationToken) Method

Definition

Retrieves a proffered service asynchronously; otherwise, null if it could not be retrieved.

public System.Threading.Tasks.Task<T?> GetValueOrNullAsync (System.Threading.CancellationToken cancellationToken = default);
abstract member GetValueOrNullAsync : System.Threading.CancellationToken -> System.Threading.Tasks.Task<'T (requires 'T : null)>
Public Function GetValueOrNullAsync (Optional cancellationToken As CancellationToken = Nothing) As Task(Of T)

Parameters

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 expediant cancellation of the returned Task.

Returns

Task<T>

A task whose result is one of the following:

  • The service if the request was successful.
  • null if the service threw an exception during activation. InnerException may include details about the underlying failure.
  • null if the associated package failed to load. InnerException may include details about the underlying failure.
  • null if the associated package proffered null.
  • null if the associated package could not be found, or the package did not correctly proffer the service.
  • null if the environment has starting shutting down and the retrieval would have resulted in a package load.
  • Otherwise; null if there was any other failure retrieving the service.true.

Exceptions

cancellationToken has been canceled.

Remarks

This method is safe to access from any thread.

Applies to