You can change the value of an attribute in JavaScript when the page is finished loading by using the window.onload event. Here’s an example that changes the value of an attribute called data-example for an element with an ID of “element_id”:
javascript
window.onload = function() {
document.getElementById(“element_id”).setAttribute(“data-example”, “new_value”);
};
The window.onload event is fired when all of the resources for a page have finished loading, including images, scripts, and stylesheets. This ensures that the element with the specified ID is available in the DOM and can be manipulated by JavaScript.