import { Injectable } from '@angular/core'; import { TaxRateService } from './tax-rate.service'; @Injectable() export class SalesTaxService { constructor(private rateService: TaxRateService) { } getVAT(value: string | number) { let amount = (typeof value === 'string') ? parseFloat(value) : value; return (amount || 0) * this.rateService.getRate('VAT'); } }