TheThing..::..RegisterForUpdateHistory Method (Int32, TimeSpan, List<(Of <(<'String>)>)>, List<(Of <(<'String>)>)>, TimeSpan, Boolean, Boolean)
Note: This API is now obsolete.
Assembly: C-DEngine (in C-DEngine.dll)
Gathers history for property changes to the TheThing according to the filters specified in the parameters. Returns a token that can be used to retrieve history items for the filter.
Each independent consumer needs to obtain a token of their own.
Tokens can be reused across restarts if permanent=true is specified. Otherwise a new token must be obtained after a restart.
Tokens must be unregistered when the history filter is no longer needed in order to free up system resources, especially if the consumer was registered as permanent.
Namespace:
nsCDEngine.Engines.ThingServiceAssembly: C-DEngine (in C-DEngine.dll)
Syntax
[ObsoleteAttribute] public Guid RegisterForUpdateHistory( int maxCount, TimeSpan maxAge, List<string> properties, List<string> propertiesToExclude, TimeSpan propertySnapshotWindow, bool reportUnchangedProperties, bool permanent )
Parameters
- maxCount
- Type: Int32
Indicates the maximum number of history items to store. Specify 0 to not limit the number of items.
- maxAge
- Type: TimeSpan
Indicates how far back in time to retain history items. Specify TimeSpan.Zero for not time limit.
- properties
- Type: List<(Of <(<'String>)>)>
List of properties to include in history items. Set to null to include all properties.
- propertiesToExclude
- Type: List<(Of <(<'String>)>)>
List of properties to not include in history items. Use with properties = null.
- propertySnapshotWindow
- Type: TimeSpan
Granularity for history items. The state of the item at the end of the time window is returned as a history item.
- reportUnchangedProperties
- Type: Boolean
If set to true, also includes unchanged properties in the history item. If set to false (default), only changed properties are included.
- permanent
- Type: Boolean
Set to true to keep the history across restarts. The history token remains valid across restarts.