Public Overloads Function ReadAtTime( _
   ByVal timeStamps() As Date, _
   ByVal server() As Integer, _
   ByRef itemValues As OPCHDAitem(), _
   ByRef errors As Integer() _
) As Integer

public int ReadAtTime( 
   DateTime[] timeStamps,
   int[] server,
   out OPCHDAitem[] itemValues,
   out int[] errors
)

Parameters

timeStamps

The timestamps for the requested data.

server

The list of server item handles for the items to be read.

itemValues

OUT: Array of structures in which the item values are returned. The order of the structures in the array shall be the same as the order of the server item handles.

errors

OUT: Array of HRESULTs indicating the success of the individual item reads. The errors correspond to the handles passed in server. This indicates whether the read succeeded in obtaining a defined value, quality and timestamp. NOTE that any FAILED error code indicates that the corresponding OPCHDAitem struct is undefined.

Return Value

The order of the values and qualities returned shall match the order of the time stamps supplied in the request.

When no value exists for a specified timestamp, a value shall be interpolated from the surrounding values to represent the value at the specified timestamp.

The interpolation will follow the same rules as the standard Intpolated aggregate as outlined in specification Section 2.9 The OPCHDAitem structure will return OPCHDA_NOAGGREGATE in the aggregate field. If a value is found for the specified timestamp, the server will set the OPCHDA_RAW bit in the quality. If the value is interpolated from the surrounding values, the server will set the OPCHDA_INTERPOLATED bit in the quality.

Target Platforms: Windows 7/8/10, Windows Server 2008/2012/2016, .NET 4.x

Reference