Collection was modified; enumeration operation may not execute - why?

Posted by contactmatt on Stack Overflow See other posts from Stack Overflow or by contactmatt
Published on 2010-12-27T00:53:56Z Indexed on 2010/12/27 1:53 UTC
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c#

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enumeration

I'm enumerating over a collection that implements IList, and during the enumeration I am modifying the collection. I get the error, "Collection was modified; enumeration operation may not execute."

I want to know why this error occurs when modifying a item in the collection during iteration. I've already converted my foreach loop to a for loop, but I want to know the 'details' on why this error occurs.

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