A fully-featured listener interface, which receives notification of data updates and subscription termination for a table. 

Upon update of each item, the current and previous state of all fields is provided. If the subscription configuration enables the "COMMAND logic", then the special "key" and "command" fields are determined and the updates are meant as ADD, UPDATE and DELETE commands on the rows of an underlying table, identified by a key value. In this case, the old field values related with an update are referred to the same key. 

Both names and positional information are available to identify specific items and fields, unless a SimpleTableInfo was used to describe the table; in that case, only positional information is available. 

Positional information refers to the "TableInfo" object used to specify the subscription request. Note that if "SubscribeItems" was used, this may not represent an actual table but just an item list. 

The listener is called directly from the worker threads. The method implementations should be fast and nonblocking. Any slow operations should be enqueued and performed asynchronously. 

public: __interface IHandyTableListener;

public interface IHandyTableListener;

Public Interface IHandyTableListener