class to connect to an OPC AE Server
TdOPCEventServer is a component to control, browse, read and write data from an to any installed OPC Alarm and Event server.

TdOPCCOMAEConnection is derived from TdOPCCOMConnection.

class for one Event from OPC Server
TdOPCEvent represents an event sent by the TdOPCEventServer.

TdOPCEventAreaBrowser provides a way to browse the process area organization implemented by the server.

TdOPCEventCondition provides the current state of events.

TdOPCEventCustomProps contains and manages a collection of custom properties.

TdOPCEventFilter represents a single event subscription.

TdOPCEventFilters contains and manages a collection of TdOPCEventFilter objects.

TdOPCEventItem can store information about categories, conditions, (vendor) attributes and subconditions which are all event items.

TdOPCEventItems contains TdOPCEventItem objects.

class for internal use to store sort items
TdOPCEventSortItem is used to store sort items.

TdOPCEventSubCondition provides one substate of a TdOPCEventCondition.

TdOPCEventSubConditions is derived from TList.

class to receive IConnectionPointContainer event callbacks
TdOPCEventSubscription is delivered by an OPC AE server to manage a single event subscription.

class for OPC Server events (see also TdOPCEvent)
TdOPCEvents represents a collection of TdOPCEvent objects.

TOndOPCAckEvent is used for OnEventAck.

TOndOPCEvent is used for OnEvent and OnDeleteEvent.

TSortProc is a procedural type to provide the ability to sort the passed parameters Item1, Item2.

tdOPCEventtypes contains options to set the TdOPCEventFilter.EventType.