I took a look and it seems that it's pretty much hardcoded that the address space tree levels are using a single character and the customisations are not really possible without modifications to the components.

Regarding arrays, there is no specific handling for the array elements, so you would need to break them up yourself. In your case, it seems even that the array elements are in the middle of the tree, which makes it even more tricky.

If you find a way to customise these in your code - or how the component interface could be improved to support this in practice, I would be happy to hear, though.

To explain briefly, in that system items are defined as:
(IP address)!(expression)
For example:
LocalHost!R[10]
192.168.1.10!Task1.P[4].Counter

I wanted to take advantage of the new browsing possibilities to move to a space modelling this

192.168.1.10
    + Task1
        + P
           + [1]
           + [2]
           + [3]
           + [4]
               + Counter

Defining the hierarchy is not a problem, but for the client the resulting item is :
192.168.1.10.Task1.P.[4].Counter

I can make the system tolerant and accept this syntax as well, and then correct it in the FindItem event, but before I do that I would have liked a confirmation that there is no other possible solution to define this Fullpath in a custom way.

Another question, is there a "good" way to handle arrays and allow access in the browser to different index values?

Thanks in advance

Are you already using the latest version 7.3.0?

Unfortunately this doesn't seem to work, I do create the exception you indicated, but despite this the client receives a success status.

I am coming to the end of the one month trial extension tomorrow. I'll probably have to stop testing, as I don't know when we'll order the licenses from you, hopefully next week. I would ask you for another extension, but I'm afraid I'm taking it a bit too far ? Anyway, thank you for your support until now.

The client info should be available from TUaServer.SessionManager, but it only provides SessionCount at the moment.

My OPC UA server is almost functional, but I'm still missing some small details.

- To forbid the writing of a TUaVariable by the client, AccessLevel must contain [altCurrentRead], is that right? But the variable is still accessible and modified by the client.

- How do we get the information about the connected clients (IP address, name of the client software, others)?

In any case, at the moment the solution is to create your own version of a NodeManagerUaNode and override methods in there. You could override TryGetNode, which is used whenever a node is looked up by it's NodeId.

So at the moment you will have to do the mapping yourself from TPsVars to TUaVariables.

I will now switch to UA. Will I be able to set up a system that works in a similar way? Will the TPsVar descendant objects used for the DA server work the same way for UA?

Thank you in advance

But, basically, you can define the contents of the AddressSpace as you like.

By default, the AddressSpace will be filled with variables that are found in all forms and data modules that are added to the Application. You can use 'PsOPCProvider.AddressSpace.AutoAddApplication := False;' to disable this default logic. Use AddVariable(s) to add what you need in there. You can provide a custom name for each to be used in the address space. This is probably the easiest way to do it. See the help for 'TPsOPCProviderAddressSpace'.

You will only need to use OnFindItem, if you wish to create variables dynamically, upon client request, instead of predefining everything.