问如何在Firestore中删除收藏中的所有文档

EN

// add ${documentReference} that contains / may contains the ${collectionsList}
_recursiveDeleteDocumentNestedCollections(
      DocumentReference documentReference, List collectionsList) async {
    // check if collection list length > 0
    if (collectionsList.length > 0) {
      // this line provide an async forEach and wait until it finished
      Future.forEach(collectionsList, (collectionName) async {
        // get the collection reference inside the provided document
        var nfCollectionRef = documentReference.collection(collectionName);
        try {
          // get nested collection documents
          var nestedDocuemtnsQuery = await nfCollectionRef.getDocuments();
          // loop through collection documents 
          Future.forEach(nestedDocuemtnsQuery.documents, (DocumentSnapshot doc) async {
            // recursive this function till the last nested collections documents
            _recursiveDeleteDocumentNestedCollections(
                doc.reference, collectionsList);
            // delete the main document
            doc.reference.delete();
          });
        } catch (e) {
          print('====================================');
          print(e);
          print('====================================');
        }
      });
    }
  }