Question

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for vs foreach vs while which is faster for iterating through arrays in php

For each and while, which of these is faster, recommended, and what are their resource usages like?

Answer 1

foreach is optimized for iteration over collections. That’s a fancy way of saying that it works best (and fastest) when you use it with arrays (and as of PHP5, objects). You can use while() to get the same effect as a foreach, but its not as efficient since you need to call list() inside the while loop.

foreach($array as $key => $value) written with a while is while(list($key,$value) = each($array)). You can see the number of extra calls that are needed.