The Visavi.Opc.Client namespace contains interfaces and classes that define various objects, that may be used to design and implement OPC aware applications.
| Class | Description |
|---|---|
| AsyncIoNotAvailableException | Exception that occurs when an asynchronous write is called and the corresponding interface is not available from the OPC Server. |
| BrowseItemException | Exception that occurs when an irrevocable error occurs while browsing a particular item on the OPC Server. |
| GroupArgs | Provides data for the GroupAdded and GroupRemoved events. |
| ItemArgs | Provides data for the ItemDefinitionChange and ItemRuntimeChange events. |
| OpcConnection | Component that implements the IOpcConnection interface. This component may be used in forms to access communication with OPC servers. |
| OpcGroupDefinition | Defines an object to be added to the IOpcGroupCollection. |
| OpcItemDefinition | Defines an object to be added to the IOpcItemCollection. |
| OpcServerConnectException | Exception occurs when an error occured in connecting to the specified OPC Server. |
| OpcTransaction | Represents an asynchronous transaction with the OPC Server. |
| TimeoutException | Exception occurs when a timeout occurs in a synchonous call to the OPC Server. |
| WriteCompleteArgs | Provides data for the WriteComplete event. |
| WriteTimeoutArgs | Provides data for the WriteTimeout event. |
| WriteTransaction | Represents an asynchronous write transaction with the OPC Server. |
| Interface | Description |
|---|---|
| IOpcBrowseElement | Defines the representation of an element used in browsing an OPC Server's address space. |
| IOpcConnection | Defines the representation of a connection to an OPC Server. |
| IOpcGroup | Defines the representation of a group that exists in an OPC Server. |
| IOpcGroupCollection | Defines a collection container for instances of the IOpcGroup interface. |
| IOpcItem | Defines the representation of an item that exists in an OPC Server. |
| IOpcItemAttributes | Defines a representation of attributes for an IOpcItem. |
| IOpcItemCollection | Defines a collection container for instances of the IOpcItem interface. |
| IOpcItemDefinition | Defines the design-time properties of an IOpcItem interface. |
| IOpcItemProperty | Defines the representation of an item's property. |
| IOpcItemPropertyCollection | Defines a collection container for instances of the IOpcItemProperty interface. |
| IOpcItemRuntime | Defines the runtime properties of an IOpcItem interface. |
| IOpcServerStatus | Defines the status of an OPC Server. |
| IOpcValue | Defines the representation of an OPC data value. |
| Structure | Description |
|---|---|
| OpcDataType | Encapsulates the data-type of an IOpcValue object. |
| OpcHResult | Encapsulates a HRESULT that may have been returned by one of the methods of the OPC Server. |
| OpcQuality | Encapsulates the data quality of an IOpcValue object. |
| OpcPropertyID | Represents the Property ID of IOpcItemProperty object. |
| WriteCompleteArgs.Result | Defines the result of a single asynchronous write operation. |
| Structure | Description |
|---|---|
| AccessPathChangeDelegate | Represents a method that handles a change in an item's access path. |
| ActiveChangeDelegate | Represents a method that handles a change in an item's active state. |
| ClientHandleChangeDelegate | Represents a method that handles a change in an item's client handle. |
| GroupAddedDelegate | Represents a method that handles the event of adding a group to the group collection. |
| GroupRemovedDelegate | Represents a method that handles the event of removing a group from the group collection. |
| ItemAddedDelegate | Represents a method that handles the event of adding a item to the item collection. |
| ItemDefinitionChangeDelegate | Represents a method that handles a change in any part of an item's definition. |
| ItemIdChangeDelegate | Represents a method that handles a change in an item's item ID. |
| ItemRemovedDelegate | Represents a method that handles the event of removing a item from the item collection. |
| ItemRuntimeChangeDelegate | Represents a method that handles a change in any part of an item's runtime data. |
| WriteCompleteDelegate | Represents a method that handles the completion of an asynchronous write operation. |
| WriteTimeoutDelegate | Represents a method that handles the timeout of an asynchronous write operation. |
| Structure | Description |
|---|---|
| BrowseElementFlags | Flags that indicate whether a browse element is an item, has children, or both. |
| BrowseFilter | Specifies a filter for browsing. |
| ConnectionScheme | Specifies when a connection should be made to an OPC Server. |
| EUType | Defines the type of engineering units for an item. |
| OpcDataType.Enumeration | An enumeration of common types for the OpcDataType structure. |
| OpcHResult.Enumeration | An enumeration of common result values for the OpcHResult structure. |
| OpcPropertyID.Enumeration | Represents the Property ID of IOpcItemProperty object. |
| OpcQuality.Enumeration | An enumeration of common quality values for the OpcQuality structure. |
| OpcQuality.FieldFlags | An enumeration of common quality values for the OpcQuality structure. |
| OpcQuality.LimitFlags | An enumeration of common quality values for the OpcQuality structure. |
| OpcServerState | Defines the state for an OPC Server. |
| WriteMethod | Defines the method (synchronous or asynchronous) used for writing a value to an OPC item. |
See Also