What is Virtual DOM? What is the main difference between DOM and Virtual DOM?
Summary
What is Virtual DOM? How does it differ from Real DOM, and what are its main functions? Let's explore these in detail.
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Virtual DOM
React.js
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what-is-virtual-dom
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The Virtual DOM is a concept used in frontend libraries like React, designed to speed up working with the DOM (Document Object Model). The Virtual DOM is essentially a virtual version of the DOM, optimized to handle changes and improve the efficiency of rendering the page.
DOM (Document Object Model)
The DOM represents the structure of HTML documents as a programming interface. When a web page is created, the browser generates this page as a DOM object. The DOM is a tree-like model that describes the data structure and the relationships between elements. Working with the DOM involves tasks like making changes to elements on the page, updating data, and more, typically using JavaScript.
Virtual DOM
The Virtual DOM is the latest version of the DOM used in React and other frontend libraries. It acts as a lightweight, memory-efficient version of the DOM. Its primary goal is to speed up the process of working with the DOM and improve performance.
Differences between Virtual DOM and DOM:
Updating Data:
DOM: When working with the DOM, any changes are directly reflected on the page. This may require multiple re-renders and page reloads.
Virtual DOM: In the Virtual DOM, changes are first made in the virtual version, then optimally applied to the real DOM, minimizing the actual updates.
Performance:
DOM: Updating the DOM can often be slow, as it may require re-rendering a large number of elements.
Virtual DOM: The Virtual DOM tracks changes and updates only the necessary parts, improving efficiency.
Reevaluating Changes:
DOM: Revisiting and updating changes in the DOM can take significant time.
Virtual DOM: In the Virtual DOM, changes are first applied virtually, then a diffing algorithm determines what needs updating, and only minimal changes are sent to the real DOM.
In summary, the Virtual DOM speeds up working with the DOM and efficiently manages changes, ensuring that frontend applications run fast and smoothly.