Mastering React State Management: From Local to Global
Tags: react, webdev, javascript, advanced
Published: 2023-09-15 11:02:43

Welcome to the exciting world of state management in React! As developers, we know that handling state is a fundamental part of building robust web applications. In React, we have a multitude of options to manage state effectively, each tailored to different scenarios. Let's embark on a journey to explore these state management techniques and gain a deeper understanding of where and when to use them.

**Understanding Types of State**

To begin our journey, let's classify state based on accessibility and domain:

**A. State Accessibility:**

**1. Local State:** This type of state is specific to one or a few components and is accessible only to their child components.
**2. Global State:** Here, state is needed by multiple components, and it's accessible throughout the entire application.

**B. State Domain:**

**3. Remote State:** When all application data is loaded from a remote server (usually an API), it's considered remote state. This data is typically asynchronous and requires fetching and updating.

**4. UI State:** UI state encompasses everything else, such as themes, filters, form data, and more. These states are usually synchronous and are stored within the application.


**State Placement Options**

Now that we understand the types of state, let's explore where we can place them:

**- Local Components:** Use `useState`, `useReducer`, or `useRef` for managing state within a specific component.

**- Parent Components:** Lift state up to a parent component when needed. Utilize `useState`, `useReducer`, or `useRef`.

**- Context:** For global state, particularly UI state, leverage `Context API` combined with `useState` or `useReducer`.

**- 3rd Party Library:** If you require global state, consider using libraries like `Redux`, `React-Query`, `SWR`, `Zustand`, and others.

**- URL:** When you need to pass global state between pages, `React-Router` provides the tools you need.

**- Browser:** For storing data in the user's browser, use `local storage` or `session storage`.


**Managing Different Types of State**

Now, let's get practical. Here's how to manage different types of state in practice:

**Local UI State:** Use `useState`, `useRef`, or `useReducer` for handling local UI state within a component.

**Local Remote State:** In smaller applications, you can use `fetch()` combined with `useEffect()` and `useState()` or `useReducer()` to manage local remote state.

**Global UI State:** For global UI state, `Context API` combined with `useState()` or `useReducer()` is a powerful choice. You can also explore libraries like `Redux`, `Zustand`, `Recoil`, and even `React-Router` for navigation-based UI state.

**Global Remote State:** When dealing with global remote state, consider using `Context API`, `fetch()`, `useEffect()`, and `useState()` or `useReducer()`. Specialized tools like `React-Query`, `SWR`, and `RTK Query` can further streamline remote global state management.

This comprehensive guide equips you with the knowledge to choose the right state management approach for your React applications. Whether you're handling local UI state or managing global remote state, understanding these techniques will make you a more proficient React developer. 🚀🔗

Explore, experiment, and elevate your state management skills. Happy coding!