Returns a snapshot of the number of items in the specified region.
key
Key name. If this parameter is not null, then this method will return information on this item only. This can be used to check
if the item has expired but not yet purged from the cache. If this parameter is null, then information on all the items in regionName is returned.
regionName
Region name. If this value is not null, then this method will return information on the items in this region. If this
parameter is null, then information on all regions in the cache is returned (the equivalent of calling GetStatistics.
A CacheStatistics object containing the current number of regions, items and expired items in the cache.