In the Debit method, since you are check the amount against both overdraft + savings account balance, you most like want to send the combined balance in the OverdrawnEventArgs. So, I think this

OnOverdrawn(new OverdrawnEventArgs(Balance, amount));

should be

OnOverdrawn(new OverdrawnEventArgs(Balance + SavingsAccount.Balance, amount));

That could very well be. I actually don't know what the rules are for an overdraft account so I just sort of made it up.

It might be even more useful to pass the account objects as OverdrawnEventArgs properties so the main program could examine the two accounts and figure out what to do about them. That gives the main program the greatest flexibility because it can determine any of the balances it needs to know.

(Aside: In real life, I've heard some nasty stories about banks doing things like ordering monthly debits in decreasing order. For example, suppose you have $100 in your account and you write checks for $100, $50, $20, and $15. If you try to pay them in that order, the first one cleans out the account so you get hit with 3 overdrawn charges. If you pay them in the order $15, $20, $50, $100, then you can pay the first three and only one is overdrawn. I think the ordering-to-maximize-charges strategy is now illegal.)

__________________
Rod

Rod Stephens, Microsoft MVP

Essential Algorithms: A Practical Approach to Computer Algorithms

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