Enumeration Classes - Part 1 (PaymentType Enum - PaymentTypeExtensions)

PaymentTypeExtensions.cs

public static class PaymentTypeExtensions
{
    public static string GetPaymentTypeCode(this PaymentType paymentType)
    {
        switch (paymentType)
        {
            case PaymentType.CreditCard:
                return "CC";
            case PaymentType.DebitCard:
                return "DC";
            default:
                throw new ArgumentOutOfRangeException(
                    nameof(paymentType), paymentType, "Invalid payment type");
        }
    }
}