Visual Basic (Usage)	Copy Code
Dim instance As Session Dim nodesToRead As IList(Of HistoryReadValueId) Dim details As ReadAtTimeDetails Dim timestampsToReturn As TimestampsToReturn Dim settings As RequestSettings Dim callback As AsyncCallback Dim userData As Object Dim value As IAsyncResult value = instance.BeginHistoryReadAtTime(nodesToRead, details, timestampsToReturn, settings, callback, userData)

public IAsyncResult BeginHistoryReadAtTime( 
   IList<HistoryReadValueId> nodesToRead,
   ReadAtTimeDetails details,
   TimestampsToReturn timestampsToReturn,
   RequestSettings settings,
   AsyncCallback callback,
   object userData
)

Parameters

nodesToRead

List of variable nodes to read data values at specified timestamps from.

details

Configuration parameters for the history read of data at specified timestamps. Configuration parameters include - Array of timestamps for which values are to be read - Flag for bounding value calculation

timestampsToReturn

Enumeration for the timestamps to return with the values. Possible values are source, server or both. The option neither is invalid for history read.

settings

The general settings for the request. If null, the default settings from the property #DefaultRequestSettings are used.

callback

The callback to use when the async call completes.

userData

The user data that is passed to the callback.

Return Value

Target Platforms: Windows 7/8/10, Windows Server 2003/2008/2012/2015, .NET4.x

Reference