OpcLabs.EasyOpc.DataAccess Namespace (OpcLabs.EasyOpcClassicCore)

This namespace contains classes that facilitate easy work with OPC Data Access.

Classes

	Class	Description
	DAAccessRight	Indicates if the item is read only, write only or read/write.
	DABrowseParameters	Contains filtering conditions for OPC Data Access node browsing.
	DAGroupParameters	Contains subscription parameters, such as the requested update rate.
	DAItemDescriptor	Contains information necessary to identify an OPC item, such as its Item Id.
	DANodeDescriptor	Contains information necessary to identify an OPC Data Access node, such as its Item Id.
	DAPropertyDescriptor	Contains information necessary to identify an OPC property, such as its Property Id.
	DAPropertyId	The identifying number assigned by the OPC server to the property.
	DAQuality	Represents the quality state for an item's data value.
	DAReadParameters	Contains parameters for OPC read operations, such as the data source or value age.
	DAUtilities	Contains static members that facilitate work with types related to OPC Data Access.
	DAVtq	Holds data value, timestamp and quality, abbreviated sometimes as VTQ. This is a common combination in OPC, e.g. returned when an OPC item is read.
	EasyDAUriStrings	Contains URI strings used by OPC-DA client object.
	IEasyDAClientExtension	Contains extension methods to the IEasyDAClient interface.

Interfaces

	Interface	Description
	IEasyDAClient	Allows simple access to OPC Data Access servers.
	IEasyDAClientDequeuing	Provides access to dequeuing for IEasyDAClient objects.
	IEasyDAClientSettings	Provides access to settings for IEasyDAClient objects.

Delegates

	Delegate	Description
	EasyDAItemChangedEventHandler	Represents the method that will handle an event raised for every significant change in a subscribed OPC item.

Enumerations

	Enumeration	Description
	DAAccessRights	Contains pre-defined constants of DAAccessRight internal values.
	DABrowseFilter	An enumeration specifying which subset of browse elements to return.
	DADataSource	Selects the data source for OPC reads (from device, from OPC cache, or dynamically determined).
	DALimitChoice	The Limit bit field of OPC quality.
	DAPropertyIds	Contains pre-defined constants of DAPropertyId internal values.
	DAQualities	Contains pre-defined constants of DAQuality internal values.
	DAQualityChoice	The QualityChoice bit field, i.e. the most significant part of the OPC quality flags.
	DAStatusChoice	Status is a combination of QualityChoice and Substatus. Which Substatus values can be used depend on QualityChoice.

Reference

OpcLabs.EasyOpcClassicCore Assembly

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