document.getElementById("#"); Not Working

Question

I am trying to replace:

function checkValue() {
    if (remainingTime < 10) {
        document.getElementById("leading-zero").style.display = "inline";
    } else {
        document.getElementById("leading-zero").style.display = "none";
    }
}

..with this:

var leadingZero = document.getElementById("leading-zero");

function checkValue() {
    if (remainingTime < 10) {
        leadingZero.style.display = "inline";
    } else {
        leadingZero.style.display = "none";
    }
}

The first block of code works just fine but I don't want to be accessing the DOM everytime checkValue() is called (every half a second). That's why I attempted assigning the object (is it called an object??) to the variable named leadingZero. Why will this not work??

`The first block of code works just fine` It shouldn't, it should throw a `SyntaxError`. — CertainPerformance, Jun 15 '18 at 03:55
need to run `document.getElementById("leading-zero");` after the element is created — Arun P Johny, Jun 15 '18 at 03:55
@CertainPerformance oops sorry I need to fix that... I was just trying to type the question quickly and messed it up. — The Demon Hunter, Jun 15 '18 at 03:56
I really don't recommend _typing_ question code. You should copy / paste it from your actual code — Phil, Jun 15 '18 at 03:57
@Phil I was going to.. but I have a heap of unrelated code mixed in as well (which is totally irrelevant). — The Demon Hunter, Jun 15 '18 at 03:57

Facundo Larrosa · Answer 1 · 2018-06-15T04:03:07.660

0

Instantiate leadingZero after document is loaded:

var leadingZero;
document.addEventListener("DOMContentLoaded", function(){
     leadingZero = document.getElementById("leading-zero");
);

function checkValue() {
    if (remainingTime < 10) {
        leadingZero.style.display = "inline";
    } else {
        leadingZero.style.display = "none";
    }
}

edited Jun 15 '18 at 04:03

answered Jun 15 '18 at 03:58

Facundo Larrosa

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Why is it wrong? – Facundo Larrosa Jun 15 '18 at 03:58
_"I don't want to be accessing the DOM everytime checkValue() is called"_ – Phil Jun 15 '18 at 03:58

document.getElementById("#"); Not Working

1 Answers1