| 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.
The BrowseBranches methods return the branches available under the specified parent branch in the OPC-DA address space. The server(s) can be local or can be remotely accessed via DCOM. |
| BrowseLeaves | Overloaded. Browses the specified branch (or root) in OPC server's address space, and returns information about child leaves found.
The BrowseLeaves methods return the leaves available under the specified parent branch in the OPC-DA address space. The server(s) can be local or can be remotely accessed via DCOM. |
| 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. Browses for available OPC (Data Access) servers.
The server(s) can be local or can be remotely accessed via DCOM. |
| 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. The server(s) can be local or can be remotely accessed via DCOM. |
| GetPropertyValue | Overloaded. Gets a value of OPC property of a specified OPC item.
The server(s) can be local or can be remotely accessed via DCOM. |
| 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 an OPC-DA item. Value, quality and timestamp are returned.
The ReadItem method reads the data of an OPC-DA item. It uses the first available data from the server; it does not wait until the quality becomes "uncertain" or "good". The server(s) can be local or can be remotely accessed via DCOM. Optionally, a specific data type can be requested, or an access path can be specified (OPC DA 1.0 only). |
| ReadItemValue | Overloaded. Reads an OPC-DA item value.
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 requires that the value quality is "good". The server(s) can be local or can be remotely accessed via DCOM. Optionally, a specific data type can be requested, or an access path can be specified (OPC DA 1.0 only). |
| ReadMultipleItems | Overloaded. Reads data of multiple OPC-DA items.
The ReadMultipleItems method reads the data (values, timestamps and qualities) of multiple items from one or more OPC-DA servers. It uses the first available data from the server for each item; it does not wait until the quality becomes "uncertain" or "good". 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. The server(s) can be local or can be remotely accessed via DCOM. Optionally, a specific data type can be requested, or an access path can be specified (OPC DA 1.0 only). This method operates on multiple items at once. If you only have one item, you can use the ReadItem(IEasyDAClient,DAReadItemArguments) method instead. |
| ReadMultipleItemValues | Overloaded. Reads values of multiple OPC-DA items.
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. The server(s) can be local or can be remotely accessed via DCOM. Optionally, a specific data type can be requested, or an access path can be specified (OPC DA 1.0 only). |
| 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 The server(s) can be local or can be remotely accessed via DCOM. |
| SubscribeMultipleItems | Overloaded. Subscribe to changes of multiple OPC items.
The ItemChanged event will be generated for each significant item change. |
| 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(s) can be local or can be remotely accessed via DCOM. Optionally, a specific data type can be requested, or an access path can be specified (OPC DA 1.0 only). |
| 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 WriteItemValue only writes the item value into the OPC-DA server; how the quality and timestamp are affected depends on the server. Some servers support writing the quality and timestamp as well; use the WriteItem method for that. The server(s) can be local or can be remotely accessed via DCOM. Optionally, a specific data type can be requested, or an access path can be specified (OPC DA 1.0 only). |
OPC Studio User's Guide and Reference
IEasyDAClientExtension Class Members
