Do something if is the last iteration of the arrayĬonsole.log('Last iteration with item : ' + item) Īs the while loop will start iterating from the last item (in the example the item 'd'), we need to check if the value that decreases (the counter of the index to handle) is equal to 0. If these values are equal, then it's the last iteration.įor example, to check within a for loop you only need to check the previous rule using an if statement: var group = With a myriad of HTTP utility methods and middleware. Based on this number, we will make a comparison between the length of the array (total items inside) and the current iteration index (the index of the item inside of the array) plus one, because as everybody knows, the first element of the array is always 0 as it's exactly contained in the memory location that array refers (0 elements away). In short, for.in iterates over the enumerable properties of an object, while for.of iterates over 'iterable collections'. Ready to try JavaScript Begin learning here by typing in your first name surrounded by quotation marks, and ending with a semicolon. js web application framework that provides a robust set of features for web and mobile applications. To check wheter an iteration is the last in the loop or not, we only need to know the length of the array. The comparison that we need to make to check if an iteration is the last within an array, can vary according to the way you iterate.

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