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why is this temporary variable needed?

Posted By:      Posted Date: September 15, 2010    Points: 0   Category :ASP.Net
right at the very top, first paragraph of this:http://www.albahari.com/nutshell/predicatebuilder.aspxforeach (string item in items){     string temp = item;     //now works with temp, instead of item}why would this be necessary? that article states:"The temporary variable in the loop is required to avoid the outer variable trap, where the same variable is captured for each iteration of the foreach loop."I don't get this? I'm definitely not up to speed with all the developments in programming over the years  but I have worked with foreach pattern many times and don't recall every having to do this? Isn't the whole point of the foreach to iterate over some collection and work with each individual item, as in 'string ITEM in items'???confused.

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