//returns the total amount for a given year, month and type public double getAmount(Invoice.InvoiceType type, int year, int month) { if (contains(type, year, month)) { MonthlyInvoice mInvoice = this.MonthlyInvoices.Find(m => m.Month == month && m.Year == year && m.Type == type); return(mInvoice.Amount); } else { return(0); } }
public void addInvoice(Invoice.InvoiceType type, int year, int month, double amount) { lock (this.MonthlyInvoices) { if (contains(type, year, month)) { MonthlyInvoice mInvoice = this.MonthlyInvoices.Find(m => m.Month == month && m.Year == year && m.Type == type); mInvoice.Amount += amount; } else { MonthlyInvoice mInvoice = new MonthlyInvoice(type, year, month, amount); this.MonthlyInvoices.Add(mInvoice); } } }