This method retrieves state information from the server for the object from which it is called and updates the local cache of information in the PI-SDK. The Refresh method acts hierarchically so a call to a particular object will also refresh that object's child objects if they have been cached.
The object placeholder is an object that evaluates to a reference to an IRefresh interface. See the Applies To table in the IRefresh definition for a list of objects that support this interface.
Refreshing PI 2.x PIUnitBatches
When PI 2.x PIUnitBatch's are closed (the EndTime is set), they can't be found by searching for some seconds depending on how fast and how busy the PI 2.x Server is. To work around this, the PI-SDK will retry for up to ten seconds to find a PI 2.x PIUnitBatch when it is refreshed. If your application can't tolerate this delay, you can perform the search yourself (using PIModule.PIUnitBatchSearch) and decide what to do if you can't find the PIUnitBatch when it is being closed. This search is the same search used by the PI-SDK when it refreshes a PI2.x PIUnitBatch.