IDataLoggerService2 Reading variable names from array records (RT DataLogger)

PLCnext Engineer
1

Hello, I have been following the RT datalogger article series on: https://github.com/PLCnext/PLCnext_RT_Datalogger
I have got it working and I am reading timestamps and values just fine, but I am wondering if there’s a (direct or indirect) way to read the variable name that’s associated with an RscType::Array record in the readValuesDelegate implementation.

Example: Arp.Plc.Eclr/MainInstance.iSineOutput
bilde.png
How do I find what the values I am reading from the DataLogger are associated with? Sure, I give the DataLogger service a list of variables to read, but how do they connect with the readValuesDelegate implementation?

2

I figured out my problem after some trial and error. Basically, as shown in the example code; you need to keep track of an ID_Number that is incremented for each valid type in the record array (not the Timestamp or ConsistentDataSeries and RecordAttribute flags). The ID_Number then corresponds to the index of the variable that is being read in the provided variableNames vector. So you can simply get the currently read variable as variableNames[ID_Number] in the ReadVariablesDataToByte method.