A Comparison of the Reactivity Concepts in Angular, React, Vue and Svelte
By Jonas Bandi
Introduction
Reactivity is an important concept in modern web development, as it allows user interfaces to update in response to changes in data or user input. In this article, we will compare the reactivity concepts in four popular JavaScript frameworks: Angular, React, Vue, and Svelte.
Angular
Angular uses a concept called change detection to achieve reactivity. It automatically detects changes to data and updates the user interface accordingly. Angular’s change detection is based on zones, which are used to track asynchronous operations and trigger change detection when needed. While this approach provides a high degree of reactivity, it can also be resource-intensive and is a common source of performance issues in Angular applications.
React
React uses a virtual DOM and a process called reconciliation to achieve reactivity. When data changes, React compares the new virtual DOM with the previous one and only updates the parts of the DOM that have changed. This approach is efficient and allows React to deliver high-performance user interfaces. Additionally, React provides a built-in state management solution called “hooks” which allows developers to manage component state and achieve reactivity in a more predictable and controlled manner.
Vue
Vue uses a reactive system based on the reactivity of JavaScript objects. When a component’s data changes, Vue automatically re-evaluates any expressions in the template that depend on that data and updates the DOM as necessary. Vue’s reactivity system is highly efficient and allows for a clear and predictable approach to managing component state and achieving reactivity.
Svelte
Svelte takes a different approach to reactivity compared to the other frameworks. It compiles the component code to highly efficient JavaScript that directly manipulates the DOM when data changes. This approach eliminates the need for a virtual DOM and reconciliation process, resulting in extremely efficient and performant user interfaces. Additionally, Svelte provides a simple and intuitive reactive declaration syntax for managing component state and achieving reactivity.
Conclusion
Each of the four frameworks we’ve discussed approaches reactivity in a different way, with varying degrees of efficiency and complexity. While Angular and React offer powerful reactivity solutions, they can be resource-intensive and complex to manage. Vue provides a clear and predictable approach to reactivity, while Svelte’s innovative approach results in highly efficient and performant user interfaces. The choice of framework for a particular project will depend on the specific requirements and performance considerations, but it’s clear that reactivity is a key factor in the success of modern web applications.
Vue <3
Svelte <3
Svelte looks like the easiest amongst all these frameworks.