The Virtual DOM. The answer is virtual DOM is much faster and efficient, here is why. Everytime the state of our application changes, the virtual DOM gets updated instead of the real DOM. In React every UI piece is a component, and each component has a state. render() is where the UI gets updated and rendered. Explaining the processes involved between traditional web development and a modern virtual DOM approach. When a state or prop within the component is updated, the render() will return a different tree of React elements. Everytime there is a change in the state of your application UI, the DOM gets updated to represent that change.

This makes the performance far better when compared to manipulating the real DOM directly. If the state of any of these elements changes, a new virtual DOM tree is created.

Thanks. When new elements are added to the UI, a virtual DOM, which is represented as a tree is created. In React, for every DOM object, there is a corresponding “virtual DOM object.” A virtual DOM object is a representation of a DOM object, like a lightweight copy. Means whenever we do an action/event the complete dom re-renders ? The whole parent subtree then gets re-rendered to give the updated UI. When state changes occur, the virtual DOM is updated and the previous and current version of virtual DOM is compared.

Frequent DOM manipulations are expensive and performance heavy. When you start learning React, the first concept to understand is Virtual DOM. First things first, DOM stands for “Document Object Model”. Real DOM. A few times I've had to bail out of the virtual dom because it was just too slow. […] in different ways: jQuery uses HTML selectors to manipulate the DOM whereas React has its own virtual DOM  which is manipulated with changes to state. Isn’t the process less smooth to create batch update and repaint compared to do sending every single state change and repaint?
The repainting of the UI is the most expensive part, and React efficiently ensures that the real DOM receives only batched updates to repaint the UI. But before we jump into Virtual DOM, let’s see what is DOM itself.

The virtual dom will have to do an expensive diff each time only to see that one element has changed. It uses the observable to detect state and prop changes. The red circles represent the nodes that have changed.

Therefore, the more UI components you have, the more expensive the DOM updates could be, since they would need to be re-rendered for every DOM update. Click to share on Twitter (Opens in new window), Click to share on Reddit (Opens in new window), Click to share on Facebook (Opens in new window), Click to share on LinkedIn (Opens in new window), Click to email this to a friend (Opens in new window), React Virtual DOM Explained in Simple English, Svelte: Is This Next-Generation JavaScript Framework Production-Ready? First things first, DOM stands for “Document Object Model”. React uses an efficient diff algorithm to compare the versions of virtual DOM. This ensures that there are minimal operations on the real DOM. React follows a batch update mechanism to update the real DOM. When a state or prop within the component is updated, the render() will return a different tree of React elements. Its not a relevant question,but if possible help me with it.I hope angular also updating the particular part of the DOM using monkey patching ,but without using virtual DOM concept? First things first, DOM stands for “Document Object Model”. The great benefit here is that as a developer, you would not need to know how the attribute manipulation, event handling or the manual DOM updates happen behind the scenes.



Once this is done, the virtual DOM calculates the best possible method to make these changes to the real DOM. It then makes sure that batched updates are sent to the real DOM for repainting or re-rendering of the UI. Now the catch is frequently manipulating the DOM affects performance, making it slow. Hence, reducing the performance cost of updating the real DOM. - Credera, How to use jQuery with React the right way - Telbitz, React vs. Angular: The Complete Comparison, 53 Python Exercises and Questions for Beginners. Therefore, the more UI components you have, the more expensive the DOM updates could be, since they would need to be re-rendered for every DOM update. The DOM is represented as a tree data structure. React Virtual DOM Explained in Simple English.
If yes, please share it with your friends and colleagues. Because of that, the changes and updates to the DOM are fast. Did you like this post?