revised: how can I access className?!

CamCode

Revised attempt at my previous question:

I am successfully adding a class to my graphic layer.... previously I was using an ID.. I console.log(myNewGraphicLayer) and it's found, the added class below: vvv

1. attributionDataUrl: (...)
2. attributionVisible: (...)
3. className: "someThing" <-----------------------------------
4. elevationInfo: (...)
5. fullExtent: (...)
6. graphics: (...)
7. hasAttributionData: (...)
8. id: (...)
9. legendEnabled: (...)
10. listMode: (...)
11. load: ƒ (e)
12. loadError: (...)

I added it this way: vvvv

    let graphicsLayer = new GraphicsLayer({

      //id: "someThing", <------- works, but I am adding many need to use class

      className: "someThing"

    });

I am perplexed, because this will work when ID is added...

const polyDrawline = map.findLayerById('someThing');

but this will not work when className is added...

const polyDrawlineS = map.findLayerByClassName('someThing');

how do I access my className?

RobertScheitlin__GISP

Cam,

     The map class does not have a method by that name.

https://developers.arcgis.com/javascript/latest/api-reference/esri-Map.html#methods-summary 

What exactly are you trying to do? Will the findLayerById not work for you?