IEasyDAClientExtension Class Members

The following tables list the members exposed by IEasyDAClientExtension.

Public Methods

	Name	Description
	BrowseAccessPaths	Browses the possible access paths of a specified OPC item. Browse for access paths. Specify machine name, server class, and item ID.
	BrowseBranches	Overloaded. Browses the specified branch (or root) in OPC server's address space, and returns information about child branches found.
	BrowseLeaves	Overloaded. Browses the specified branch (or root) in OPC server's address space, and returns information about child leaves found.
	BrowseNodes	Browses the specified branch (or root) in OPC server's address space, and returns information about child nodes (both branches and leaves) found. Browse for child nodes. Specify machine name, server class, parent item ID, and node filter.
	BrowseProperties	Browses the available properties of a specified OPC item. Browse for available item properties. Specify machine name, server class, and item ID.
	BrowseServers	Overloaded.
	ChangeItemSubscription	Overloaded. Changes parameters of a subscription to a particular OPC item. It is more efficient to change multiple subscriptions using ChangeMultipleItemSubscriptions method.
	Equals	(Inherited from object)
	GetHashCode	Serves as the default hash function. (Inherited from object)
	GetMultiplePropertyValues	Overloaded. Gets values of multiple OPC properties of a specified OPC item. This method does not throw an exception in case of OPC operation failures. Instead, the eventual exception related to each property is returned in Exception property of each returned OpcLabs.BaseLib.OperationModel.ValueResult element.
	GetPropertyValue	Overloaded. Gets a value of OPC property of a specified OPC item.
	GetType	Gets the System.Type of the current instance. (Inherited from object)
	PullItemChanged	Attempts to pull an OPC item change subscribed to by the SubscribeMultipleItems or SubscribeItem method.
	ReadItem	Overloaded. Reads a named item from an OPC server. Value, quality and timestamp are returned. 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 ReadItem method only waits for the first update from the server (or until the timeout elapses); it does not wait until the quality becomes "uncertain" or "good".
	ReadItemValue	Overloaded. Reads a named item from an OPC server. Only the item value is returned (quality and timestamp are not returned). 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. Use this method if you are only interested in the actual value of the OPC item. Use ReadItem method if you also need the quality or timestamp. The ReadItemValue method makes it very easy to obtain the actual data value with just one function call. The ReadItemValue method waits until the quality becomes "good", or the timeout elapses.
	ReadMultipleItems	Overloaded. Reads named items from an OPC server or OPC servers. Values, qualities and timestamps are returned.
	ReadMultipleItemValues	Overloaded. Reads named items from an OPC server or OPC servers. Only the item values are returned (qualities and timestamps are not returned). The servers 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 ReadMultipleItemValues method requires that the quality is "good" for each item. The function performs all individual operations in parallel, but only returns after all individual operations are completed (or their timeouts elapse). This method does not throw an exception in case of OPC operation failures. Instead, the eventual exception related to each item is returned in Exception property of each returned OpcLabs.EasyOpc.DataAccess.OperationModel.DAVtqResult element.
	SubscribeItem	Overloaded. Subscribe to changes of a particular OPC item. The ItemChanged event is generated for each significant item change. It is more efficient to subscribe to multiple items using the `SubscribeMultipleItems` method.
	SubscribeMultipleItems	Overloaded. Subscribe to changes of multiple OPC items.
	ToString	Returns a string that represents the current object. (Inherited from object)
	UnsubscribeItem	Unsubscribe from changes of a particular OPC item. Unsubscribe from OPC item, specifying its handle.
	WriteItem	Overloaded. Writes into a named item in an OPC server. Value, quality and timestamp are written. 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.
	WriteItemValue	Overloaded. Writes a value into a named item in an OPC server. Only the item value is written (quality and timestamp are not written). 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.

Top

Protected Methods

	Name	Description
	Finalize	Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from object)
	MemberwiseClone	Creates a shallow copy of the current System.Object. (Inherited from object)

Top

Reference

IEasyDAClientExtension Class
OpcLabs.EasyOpc.DataAccess Namespace