export class DataItem { private tag?: number; private data: any; constructor(data: any, tag?: number) { this.data = data; this.tag = tag; } public setTag = (tag?: number) => { this.tag = tag; }; public clearTag = () => { this.tag = undefined; }; public getTag = () => { return this.tag; }; public getData = () => { return this.data; }; }