Does querySelector return a promise?
Your doCheck function is asynchronous but neither takes a callback nor returns a promise.
How do I check if an element exists in DOM?
Check if Element Exists in DOM in JavaScript
- Use the getElementById() to Check the Existence of Element in DOM.
- Use the getElementsByClassName to Check the Existence of an Element in DOM.
- Use the getElementsByName to Check the Existence of an Element in DOM.
Should I use querySelector or getElementById?
You should opt to use the querySelector method if you need to select elements using more complex rules that are easily represented using a CSS selector. If you want to select an element by its ID, using getElementById is a good choice.
Can I use querySelector in react?
One thing that comes at the top of the list is, we should not use global selectors like document. querySelector() or document. getElementById(). Your react app may still work while having these global selectors, but it is considered as a top rated bad practice.
Why does JavaScript promise to wait until DOM element exists?
It’s a common trick in itself, often used to speed up load time, because it means no time is spent parsing scripts before moving on to the page’s actual content. It also means that the scripts will have everything that’s “before” them in the DOM ready for use.
How to wait until an element exists in JavaScript?
If the element is being dynamically added via JavaScript, it will not work and you may need to look at the other answers. Below there is an updated version that works with promises. It also “stops” if a specific number of tries is reached. Simply add the selector you want. Once the element is found you can have access to in the callback function.
How to check if an element exists in the Dom?
You can check if the dom already exists by setting a timeout until it is already rendered in the dom. Just in case the element is never shown, so we don’t check infinitely. Maybe I’m a little bit late :), but here is a nice and brief solution by chrisjhoughton, which allows to perform a callback function when the wait is over. But be careful!
When to use promise to wait in JavaScript?
Alternatively: If you’re unwilling to move all the scripts, but still willing to simply wait for the document to report ready, there’s no need for polling. See MDN’s documentation for more.