This function reads the annotations from the history database in the specified time domain for the specified item IDs. This method is intended to read annotations for an item at specified timestamps. The time domain of the request is defined by htStartTime and htEndTime. If htEndTime is less than htStartTime the data shall be returned in reverse order, with later data coming first. OPC_S_NODATA is returned only if no annotations exist over the time domain.
Overload List
| Overload | Description |
|---|---|
| ReadAnnotations(DateTime,DateTime,Int32[],AnnotationDef[],Int32[]) | Professional Edition only. This function reads the annotations from the history database in the specified time domain for the specified item IDs. This method is intended to read annotations for an item at specified timestamps. The time domain of the request is defined by htStartTime and htEndTime. If htEndTime is less than htStartTime the data shall be returned in reverse order, with later data coming first. OPC_S_NODATA is returned only if no annotations exist over the time domain. |
| ReadAnnotations(Int32,DateTime,DateTime,Int32[],Int32,Int32[]) | Professional Edition only. This function reads the annotations from the history database in the specified time domain for the specified item IDs. This method is intended to read annotations for an item at specified timestamps. OPC_S_NODATA is returned only if no annotations exist over the time domain. |
Requirements
Target Platforms: Windows XP Professional, Windows Server 2003 family, Windows Vista, Windows 7, Windows Server 2008 family