Re: How do you modify an array while iterating through it?

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From: Jon Skeet [C# MVP] (skeet_at_pobox.com)
Date: 02/17/04 

Date: Tue, 17 Feb 2004 13:37:46 -0000

Gustaf Liljegren <gustaf.liljegren@bredband.net> wrote:

<snip>

> So, the problem remaining is how to add another Account within that loop.
> The logic is:
>
> 1. See if the account already exists in the array.
> 2. If it does, add a new amount to the old one. If not, create a new account
> in the array.
>
> I'll see if I can come up with a simple example to work on.

You can't change a list while you're iterating through it. One common
solution is to build up another list containing the items you *want* to
add to the list, and then add all of them after you've finished
iterating. (You could use ArrayList.AddRange for that.) 

-- 
Jon Skeet - <skeet@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

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