Connect and share knowledge within a single location that is structured and easy to search. If we want to cancel the transition to another page, we cant do it here. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. The function that is required to be executed is given here. It displays a default alert dialogue when a web page loads completely with images and text content. How to run a function when the page is loaded in JavaScript ? 'bubbles' is missing in type '() => void'. Some time ago browsers used to show it as a message, but as the modern specification says, they shouldnt. To handle the load event, you register an event listener using the addEventListener() method: Or use the onload property of the window object: If you maintain a legacy system, you may find that the load event handler is registered in of the body element of the HTML document, like this: Its a good practice to use the addEventListener() method to assign the onload event handler whenever possible. What is the point of Thrower's Bandolier? Why do many companies reject expired SSL certificates as bugs in bug bounties? document.ready is a great alternative to window.onload if you're using jQuery. Images and other resources may also still continue loading. If we cancel the event, the browser may ask the visitor if they are sure. See rel="noreferrer" for more information. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. This blog post explains how to use cy.window () to spy on the DOM prototype to detect when the application starts adding event listeners to the DOM elements. These features include options such as the window's default size and position, whether or not to open a minimal popup window, and so forth. The minimum required value is 100. image.onload = function (this: HTMLImageElement) { const height = this.height; const width = this.width; console.log ('Image size ', [width, height]) }; Share Follow answered Dec 10, 2021 at 11:31 Alexander Poshtaruk 2,022 14 18 What a neat solution! For example, if I want to have a pop-up, should I write (directly inside the