Disabling a custom button based on NO event (state of page when loaded)

[DaveS]

I've got a tabular data page with a custom button generated by this code in the header:

<div class="right99">
<input id="ContinueButton" type="button" value="Continue" class="cbDarkTwoLineButton" onclick="window.location.href='[@app:Launch]?uID=[@field:PharmacyUmbrellaID]"/>
</div>

In the footer, I'm trying to use Javascript to set the button to disabled.  Then I've got an "if" condition (that is working based on console log tests) that would re-enable it in certain cases.  I've tried a bunch of variations of the code to disable or enable the button with no luck:

Variation 1: 
let continuebutton=document.queryselector(".ContinueButton");
continuebutton.disabled = true;

Variation 2:
document.getElementById("ContinueButton").disabled = false;

Variation 3:
ContinueButton.disabled = false;

Variation 4:
button = document.querySelector('#ContinueButton');

const enableButton = () => {
  console.log("va");
    button.disabled = false;

Variation 5:
let button=document.getElementbyID('ContinueButton');
button.disabled= true;

What does work?  If I set the button to disabled in the html section, I get the desired behavior, so I'm pretty confident it's a javascript and not a css problem.  

Would greatly appreciate any suggestions!

 

[PotatoMato]

Hi, @DaveS. Variation 2 should work, but can you provide your whole code here?

[DaveS]

Thanks, @PotatoMato!

When I started to share the full code... Well - my code was pretty messy... So I kept boiling it down and boiling it down to the bare minimum to disable the button.  And in the end I found out that I am an IDiot because I had typed getElementByID instead of getElementById...   

I really appreciate the response and the willingness to help - I think I've finally got it!

 

[Flowers4Algernon]

Hello! You may also find this forum post helpful: 

 

[Kronos]

Adding this similar thread in case it might help.

 

[Kronos]

Adding this one to the thread as well!