parent IIIF 2 / IIIF 3

[Sozialarchiv]

To get the parent independent of the iiif version I am using the following code:

if (manifestoData.context === 'http://iiif.io/api/collection/2/context.json') {
  manifestData.parent = manifestoData.getProperty('within');
} else if (manifestoData.context === 'http://iiif.io/api/presentation/3/context.json') {
  manifestData.parent = manifestoData.getProperty('partOf');
}

Is there a way without the context check?

I tried manifestData.parentCollection but it was undefined.