QuickOPC User's Guide and Reference
IEasyAEClient Interface Methods

OpcLabs.EasyOpcClassicCore Assembly > OpcLabs.EasyOpc.AlarmsAndEvents Namespace : IEasyAEClient Interface

For a list of all members of this type, see IEasyAEClient members.

Public Methods
 NameDescription
 Method

Acknowledges a condition in the Event Server. The client will receive event notifications (indicating the acknowledgement) from conditions. This method specifically acknowledges the condition becoming active or transitioning into a different sub-condition (and no other state transition of the condition). One or more conditions belong to a specific event source - the source of the event notification. For each condition-related event notification, the corresponding Source, Condition Name, Active Time and Cookie is received by the client as part of the event notification.

Uses server descriptor for specifying the OPC server. Pass in acknowledger ID and comment.

 
 MethodBrowses the specified area (or root) in OPC server's process area space, and returns information about child nodes (areas or sources) found. Uses server descriptor for specifying the OPC server. A parent area descriptor is passed in. No vendor-specific filtering.  
 MethodBrowses the specified computer and returns information about OPC (Alarms and Events) servers found.  
 Method

Changes parameters of a particular event subscription.

Changes parameters of an event subscription. Specify new notification rate, subscription filter object, and an "active" flag.

 
 MethodReturns the current state information for the condition instance corresponding to the source and condition name, passing in a server descriptor. Also allows to retrieve specified event attributes.  
 MethodObtains parameters of specified events subscription.  
 MethodGets the service object of the specified type. (Inherited from System.IServiceProvider)
 MethodDetermines whether the given event subscription handle is known to this client.  
 MethodAttempts to pull multiple OPC events subscribed to by the SubscribeEvents method. Returns refresh or standard event notifications.  
 Method

Finds out events categories supported by the server.

The QueryEventCategories method gives clients a means of finding out the specific categories of events supported by a given server. This method would typically be invoked prior to specifying an event filter. Servers are able to define their own custom event categories, but a list of recommended categories is provided in the OPC specification.

Server descriptor is used for specifying the OPC server. Queries event categories for given event types.

 
 MethodFinds out event conditions associated with the specified source name. Uses server descriptor for specifying the OPC server.  
 MethodForce a refresh for all active conditions and inactive, unacknowledged conditions whose event notifications match the filter of the event subscription.

Clients often need to get the current condition information from the server, particularly at client startup, for things such as a current alarm summary. The OPC Event Server supports this requirement by resending the most recent event notifications which satisfy the filter in the event subscription and which are related to active and/or unacknowledged conditions. The client can then derive the current condition status from the "refreshed" event notifications.  
 Method

Subscribe to particular OPC events. The Notification is generated for each event.

Subscribe to particular OPC events, using an object that holds all necessary arguments.

 
 MethodUnsubscribe from changes of all OPC events.  
 MethodUnsubscribe from particular OPC event notifications.  
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Extension Methods
 NameDescription
Public Extension MethodOverloaded. Acknowledges a condition in the Event Server. The client will receive event notifications (indicating the acknowledgement) from conditions. This method specifically acknowledges the condition becoming active or transitioning into a different sub-condition (and no other state transition of the condition). One or more conditions belong to a specific event source - the source of the event notification. For each condition-related event notification, the corresponding Source, Condition Name, Active Time and Cookie is received by the client as part of the event notification.

The server can be local or can be remotely accessed via DCOM. Optionally, an access path can be specified or a specific data type can be requested.

The client is required to pass the activeTime and cookie received in the event notification to the AcknowledgeCondition method without modification.

.NET

Public Extension MethodAcknowledges multiple conditions in the Event Server.
Public Extension MethodOverloaded. Browses the specified area (or root) in OPC server's process area space, and returns information about child areas found.

.NET

.NET

Public Extension MethodOverloaded. Browses the specified area (or root) in OPC server's process area space, and returns information about child nodes (areas or sources) found.
Public Extension Method

Browses the nodes in OPC A&E server's address space. Starts from the specified node, and returns information about child nodes found.

Browses the nodes in server's address space, given a browse arguments object.

Public Extension MethodOverloaded. Browses for OPC (Alarms&Events) servers.

.NET

Public Extension MethodOverloaded. Browses the specified area (or root) in OPC server's process area space, and returns information about child sources found.

.NET

.NET

Public Extension MethodOverloaded. Allows to traverse through OPC A&E address space nodes under the specified node, using given browse arguments.
Public Extension MethodOverloaded. Changes parameters of a particular event subscription.

.NET

Public Extension MethodAttempts to find a specified event category in the OPC server, and returns information about it when found.
Public Extension MethodAttempts to find a specified event condition in the OPC server and for given event category, and returns information about it when found.
Public Extension MethodOverloaded. Returns the current state information for the condition instance corresponding to the source and condition name.

The server can be local or can be remotely accessed via DCOM. Optionally, an access path can be specified or a specific data type can be requested.

Some servers may not maintain sufficient condition state information to fully implement this method.

.NET

Public Extension MethodAttempts to pull an OPC event subscribed to by the SubscribeEvents method. Returns refresh or standard event notifications.
Public Extension MethodOverloaded. Finds out event attributes that the server can provide as part of an event notification within a given event category. Uses server descriptor for specifying the OPC server.
Public Extension MethodOverloaded. Finds out event conditions supported by given event category. Uses server descriptor for specifying the OPC server.
Public Extension MethodOverloaded. The QueryEventCategories method gives clients a means of finding out the specific categories of events supported by a given server. This method would typically be invoked prior to specifying an event filter. Servers are able to define their own custom event categories, but a list of recommended categories is provided in the OPC specification.

.NET

.NET

Public Extension MethodFinds out event conditions associated with the specified source name. Computer name and server class are used for specifying the OPC server.
Public Extension MethodOverloaded. Subscribe to particular OPC events. The Notification is generated for each event.

.NET

.NET

Public Extension MethodOverloaded. The size of the input array will become the size of the output array. The element positions (indices) in the output array are the same as in the input array. The function returns an array of integer handles. Each such handle uniquely identifies the events subscription. The indices of elements in the output array are the same as those in the input array.
Public Extension MethodDetermines whether the client object supports a given OPC technology or technologies (such as OPC COM or OPC XML).
Public Extension Method

Unsubscribe from changes of multiple OPC events.

Unsubscribe from changes of multiple OPC events, specifying array of integer handles.

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See Also

Reference

IEasyAEClient Interface
OpcLabs.EasyOpc.AlarmsAndEvents Namespace