How can i get every nodeid when use batch list to read?

[CHN-STUDENT]

Hi, now i have i question, i try to read opc data by using batchlist, but when i try to parse datas, i do not know which data from original nodeid, so could you tell me how can i get its original nodeid?

if len(resp.Results) > 0 {
  for _, item := range resp.Results {
    // how can i get every item's original nodeid?
  }
}

[kung-foo]

The resp.Results slice will be the same length and order as the request. See: https://github.com/gopcua/opcua/blob/v0.3.13/examples/read/read.go#L41-L43. So NodesToRead[0] is returned in resp.Results[0].

[CHN-STUDENT]

Thanks! And i have anthoer question, how much nodeIDs List i can get maximum on once get?

And if i want to subscribe a nodeIDs List, how can i do？

[kung-foo]

Depends on the OPC-UA server. I usually just chunk the node list before sending read requests.

Regarding subscriptions, check out:

https://github.com/gopcua/opcua/blob/main/examples/subscribe/subscribe.go
https://github.com/gopcua/opcua/blob/main/examples/monitor/monitor.go

[CHN-STUDENT]

OK, i try to use page slice to deal with nodeIDs List, thanks for your help!