AppCaptureMetadataWriter.MetadataPurged Event

Definition

Namespace:

Windows.Media.Capture

Occurs when the system purges previously stored metadata items.

// Register
event_token MetadataPurged(TypedEventHandler<AppCaptureMetadataWriter, IInspectable const&> const& handler) const;

// Revoke with event_token
void MetadataPurged(event_token const* cookie) const;

// Revoke with event_revoker
AppCaptureMetadataWriter::MetadataPurged_revoker MetadataPurged(auto_revoke_t, TypedEventHandler<AppCaptureMetadataWriter, IInspectable const&> const& handler) const;

public event TypedEventHandler<AppCaptureMetadataWriter,object> MetadataPurged;

function onMetadataPurged(eventArgs) { /* Your code */ }
appCaptureMetadataWriter.addEventListener("metadatapurged", onMetadataPurged);
appCaptureMetadataWriter.removeEventListener("metadatapurged", onMetadataPurged);
- or -
appCaptureMetadataWriter.onmetadatapurged = onMetadataPurged;

Public Custom Event MetadataPurged As TypedEventHandler(Of AppCaptureMetadataWriter, Object) 

Event Type

TypedEventHandler<AppCaptureMetadataWriter,Object>

TypedEventHandler<AppCaptureMetadataWriter,IInspectable>

Remarks

Because historical app capture is supported, the system accumulates metadata written with AppCaptureMetadataWriter even when not actively capturing or broadcasting. When, for example, a capture of the previous 30 seconds is written to a video file on disk, the metadata associated with the recorded time window is included in the file. The system imposes a limit on the storage space that is allocated per app for storing accumulated metadata. You can get the currently available storage space by checking the RemainingStorageBytesAvailable property.

When the all of the allotted space has been filled, the system will begin purging metadata using the AppCaptureMetadataPriority value, specified when the metadata items were written, and the age of each item in order to delete the oldest, least important data first. When this occurs, the MetadataPurged event is raised. In response to this event, you may choose to reduce the amount of metadata your app is writing, but this is not required.