local values in handleData need to be attached to object

[ORESoftware]

these values:

    let index = 0;
    let prevChar = '';
    let nextNodeName = '';
    let recordingFields = false;
    let recordingNextNodeName = false;
    let recordingValue = false;
    let closingNode = false;
    let fieldName = '';
    let fieldValue = '';
    let fields = {} as { [key: string]: string };
    let nodeValue = '';

need to be:

   this.index = 0;
   this.prevChar = '';
  this.nextNodeName = '';
... etc