These properties are borderBoxSize, contentBoxSize, and devicePixelContentBoxSize, and they perfectly line up with the 3 different box model types discussed earlier. There are also 3 additional properties that all provide additional information about the width/height of the element. The most important properties are the target and contentRect since they tell you the majority of the information you need to know about which element is resizing and what its new size is. The entries array in the Resize Observer callback contains lots of useful information about the element. Const observer = new ResizeObserver ( entries => ) Resize Observer Entry In case you want to mimic the same behaviour in vanilla Javascript, here's the equivalent: var resizeId I'm personally making use of this trick on my fullPage.js library because it does a few changes on the DOM on resize.

This counter of 500 milliseconds gets restarted with every change in the window dimensions (as we clear the timeout) so the function will only be called if the user stops resizing the window OR if the user resizes the window VERY slowly, which is very unlikely :) ResizeId = setTimeout (doneResizing, 500 ) īasically what we do in this case is adding a timeout of 500 milliseconds to call our function doneResizing. For those cases we don't usually want to execute them tens of times while the user is still re-sizing the window to reach the desired size.įor these particular cases we can use a very simple trick: var resizeId

Sometimes we need to execute functions which might take a while to execute or which might consume quite a few resources from the machine.

JQuery resize event (or Javascript one) is fired when the size of the browser's window (viewport) changes as pointed out in jQuery documentation.

Resize js