Historical Events Client Overview

The Historical Events Client is a purpose-built client that demonstrates the use of Historical Events as described in UA Specifications Part 11 - Historical Access.

User Interface

Screen Elements

Menus	File Exit: Quit the application Server: Discover: See UA Discovery. Connect: Connects to the currently selected endpoint. Disconnect: Disconnects the current connection. Select Locale: For choosing a language; EN-US available only. Events: Enable Subscription: Enables/disables the subscription. Select Event Type: See Select Event Type (below). Select Event Area: See Select Event Area (below). Modify Event Filter: See Modify Event Filter (below). Edit Event History: See Edit Event History (below). Help: Contents: Launches this help documentation.
Banner	Shows the OPC Foundation logo and a [clickable] link to the website, shows the application name in large text, and shows the Certification logo with a link for more information online.
Events Area (center)	The main area of the window is a list of events that are occurring within the UA Server, and are being delivered to the client.
Endpoint Bar (below banner)	There are 3 key areas in the endpoint bar: Endpoint Url: the endpoint URL (of a Server) to connect to. Use Security: (checkbox) if checked will use a secure session, if unchecked then will use a raw/insecure session. Connect button: clicking this will attempt to connect to the specified endpoint.

Select Event Type

There are many, many different types of event (category) that are defined. You can elect to filter all event notifications to a specific type of event using this window.

Simply locate the event type (Node) and then click the OK button.

Select Event Area

You may elect to receive only the event notifications that apply to a specific area (areas are defined within the UA Server as a means of organizing events spatially).

Simply locate the area (Node) and click the OK button.

Modify Event Filter

You can further fine-tune the event filter from this dialog.

Simple right-click in the area to reveal the following context menu:

The context-sensitive menu applies to the currently selected item(s) within the list:

Display in List View	Checked = display the field within the main window event area; unchecked = hide.
Filter Enabled	Checked = selected filter is enabled; unchecked = filter is disabled.
Filter Operand	A sub-menu of logic operators such as: = < > etc.
Set Filter Value	Opens a dialog allowing to manually specify a value for the filter.
Delete Field	Delete the field from the list. (not recommended)

Click the OK button to apply the changes.

Edit Event History

From this dialog you can locate events within the historian and then delete them by using the right-click context-sensitive help menu options.