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02/16/2021
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We are using the .NET Api (version 2.1.105.1) to browse nodes in OPC UA servers, so that our customers can select which nodes to monitor. Since we are (currently) only allowing the user to monitor leaf nodes, we are having issues when nodes have properties. How is the best way to find out if a node is a “real” node, or only a property connected to a node?
05/30/2017
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The .NET API cannot connect to OPC UA servers.
It works with OPCClassic Servers only.
Can you clarify what you are trying to do?
02/16/2021
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Sorry, I did not realise that we use both the .NET Api, and the OPC UA SDK (version 1.01.333.0). The latter is of course used for connecting to OPC UA servers.
Let's take the Quickstart InformationModel Demo server "BoilerServer" as an example. When we browse the nodes, we get a tree structure. If we follow the branch Boiler #1 -> Drum1001 -> LIX001 -> Output -> EURange, "Output" is what we want to identify as the node that a customer should be able to import. Is it possible to distinguish between the property of a node (in this case EURange) and the node itself (in this case Output), based on the information we get from SessionClient.Browse?
05/30/2017
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Since we are (currently) only allowing the user to monitor leaf node.
This limitation may have made sense for COM DA client, however, it makes no sense to impose this limitation in an OPC UA client since there are not only variables with properties that contain process data, there are also variables with component variables (see https://reference.opcfoundatio.....tatusType/)
The proper way to fix this problem is to remove the "leaf" restriction and allow subscriptions to any variable in the tree.
I realize this may be technically difficult given your current design, however, any hack you do to preserve the current design will always leave some of your users complaining that they cannot subscribe to information that they should be able to subscribe to.
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