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How to Detect Page Bottom Programatically with JavaScript on Initial webpage load?

894359 asked
Last Modified: 2017-05-22
I want to know if there is a way to detect with JavaScript when I have reached the bottom of a webpage (***WHEN IT IS INITIALLY LOADNG***), right before the closing "body" tag?

I can't add any code manually/directly to ALL the HTML pages, so this needs to be handled via a JS included script therefore this is why I need to detect programatically

I want to fire a method right before the closing body tag.

The problem I'm trying to solve is that I have a bootstrap loader file that loads a js script in the head of every webpage. Every webpage is additionally supposed to have a method called immediately called, right before the closing body tag, on the initial load.
Try{ _satellite.pageBottom()}catch(e){}

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But the issue is, the bootstrap loader file will be deployed to 3rd party websites also and those sites can't put the method on their pages before the closing body tag, so trying to find a happy medium and solution. Currently I'm just doing a time delay in the bootstrap loader file to invoke the "_satellite.pageBottom() method but this is far from being close to accurate and causes timing issues.
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Distinguished Expert 2017

Try with the following code.It uses window.onscroll method and you can adjust the point at when you want to alert you or firing a function

window.onscroll = function(e) {
    if ((window.innerHeight + window.scrollY) >= document.body.offsetHeight) {
//Or another function that you want to fire.

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Hi Leonidas,
Your solution won't work. It requires scrolling and will fire every time a users scrolls to the bottom of the page.. I need something that happens while the page is loading and only once.

Distinguished Expert 2017

Υou set the px before at the point that you want to execute the code and then in your function you use the e.preventDefault or the one method


Sorry not following you? Can you provide a working example?
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Correct, I just don't think it is possible!
Thanks for the great responds!

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