How to Ensure JavaScript Executes After Page Load?

Executing JavaScript After Page Load

In certain situations, executing external scripts within the

element might hinder page functionality due to the early loading of the script. This can prevent access to elements like before the page loads completely. To address this issue, developers need to execute JavaScript after the document has loaded.

Solutions

There are several methods that can be employed to execute JavaScript after page load:

• defer Attribute: Adding the defer attribute to the <script> tag indicates that the script should be executed after the page has parsed.</script>

<script src="deferMe.js" defer></script>

• onload Event: Adding an onload attribute to the elementtriggers the execution of the provided script when the page finishes loading.

• document.onload Event: This event listener registers a function to be called once the page has loaded.

document.onload = function ...

• window.onload Event: Similar to document.onload, this event listener calls a function after the page has loaded. It is considered more standard than the previous method.

window.onload = function ...

Notes:

• Using defer or window.onload is considered good practice as it is unobtrusive.
• Event listeners like onload can be used for other page events such as resizing or scrolling.
• The body of the page should be fully loaded before executing any JavaScript to ensure all necessary elements are available.

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