How do i check if document.getElementById is null

Question

How do i go about this?

i tried doing if(document.getElementById("cart-remove")[0]) but that gives me the error: ERROR: Execution of script 'New Userscript' failed! Cannot read property '0' of null

Thanks Alot.

what people are trying to say is that `document.getElementById` returns a single element, never an array (or array-like object) - despite the number of non-unique ID's in your HTML ... you're confused with `getElementsByClassName` or `getElementsByTagName` which return a "collection" - but as you can see, the function names are `getElements` ... plural, whereas getElementById Element is singular — Jaromanda X, Nov 12 '17 at 05:15

score 1 · Answer 1 · edited Nov 12 '17 at 09:12

1

Use this code:

if(document.getElementById("cart-remove"))
{
    // some code here
}

edited Nov 12 '17 at 09:12

Brock Adams

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answered Nov 12 '17 at 05:14

Dmitriy Buteiko

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score 0 · Answer 2 · edited Nov 12 '17 at 06:49

0

you can try if (document.getElementById("cart-remove") === null) { ..... }

edited Nov 12 '17 at 06:49

daniel.gindi

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answered Nov 12 '17 at 05:13

guyz92

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score 0 · Answer 3 · answered Nov 12 '17 at 05:13

if(document.getElementById("cart-remove")){}

if document.getElementById("cart-remove") is null, then document.getElementById("cart-remove")[0] will give you an error.

You can also do:

if(document.getElementById("cart-remove") && document.getElementById("cart-remove")[0]){}

Since document.getElementById("cart-remove")[0] will give you an error if document.getElementById("cart-remove") is null, you first check document.getElementById("cart-remove") and then document.getElementById("cart-remove")[0].

score 0 · Answer 4 · answered Nov 12 '17 at 05:14

0

null is one of the falsy values in Javascript

if(document.getElementById("car-remove"))

answered Nov 12 '17 at 05:14

Shuyou

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1
5

score 0 · Answer 5 · answered Nov 12 '17 at 05:14

0

Use equality === check inside if condition

if (document.getElementById('x') === null) {
  console.log('It is null')
}

<div id="test">Test</div>

answered Nov 12 '17 at 05:14

brk

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How do i check if document.getElementById is null

5 Answers5