[Vuejs]-Reading a barcode with javascript

onInput runs every time the value changes. Most barcode scanners will simulate keypresses to enter the values they scan, so as far as your app is aware, each digit is a keypress that’s changing the value and so it reports each as an input event. An input event’s data property is just the part of the input that’s changed — so you’re getting one at a time.

You need a way to determine when the input is finished, not whenever it happens. I believe most barcode scanners will simulate pressing ENTER or TAB after a full scan is complete, so that might be what you want to detect, not with an input event, but with a keypress or keyup event.