Valtio's proxy-based state management has been discussed many times in the community, but as versions iterate, many conclusions need updating. This article revisits the topic based on the latest version.

Getting Started

Let's start with the basic implementation:

import { create } from 'zustand'
import { persist, devtools } from 'zustand/middleware'

const useStore = create(
  devtools(persist(
    (set, get) => ({
      user: null,
      theme: 'light',
      notifications: [],
      setUser: (user) => set({ user }),
      toggleTheme: () => set(s => ({
        theme: s.theme === 'light' ? 'dark' : 'light'
      })),
      unreadCount: () => get().notifications.filter(n => !n.read).length
    }),
    { name: 'app-store' }
  ))
)

This code demonstrates the basic usage. In real projects, you also need to consider error handling and edge cases.

Source Code Analysis

Building on this foundation, we can further optimize:

import { create } from 'zustand'
import { persist, devtools } from 'zustand/middleware'

const useStore = create(
  devtools(persist(
    (set, get) => ({
      user: null,
      theme: 'light',
      notifications: [],
      setUser: (user) => set({ user }),
      toggleTheme: () => set(s => ({
        theme: s.theme === 'light' ? 'dark' : 'light'
      })),
      unreadCount: () => get().notifications.filter(n => !n.read).length
    }),
    { name: 'app-store' }
  ))
)

This pattern is very practical in large projects and can significantly reduce maintenance costs.

Real-World Applications

Real-world usage is a bit more complex:

import { create } from 'zustand'
import { persist, devtools } from 'zustand/middleware'

const useStore = create(
  devtools(persist(
    (set, get) => ({
      user: null,
      theme: 'light',
      notifications: [],
      setUser: (user) => set({ user }),
      toggleTheme: () => set(s => ({
        theme: s.theme === 'light' ? 'dark' : 'light'
      })),
      unreadCount: () => get().notifications.filter(n => !n.read).length
    }),
    { name: 'app-store' }
  ))
)

Through this approach, both the testability and scalability of the code are improved.

Optimization Tips

Here is a complete example:

import { create } from 'zustand'
import { persist, devtools } from 'zustand/middleware'

const useStore = create(
  devtools(persist(
    (set, get) => ({
      user: null,
      theme: 'light',
      notifications: [],
      setUser: (user) => set({ user }),
      toggleTheme: () => set(s => ({
        theme: s.theme === 'light' ? 'dark' : 'light'
      })),
      unreadCount: () => get().notifications.filter(n => !n.read).length
    }),
    { name: 'app-store' }
  ))
)

Pay attention to boundary condition handling, which is critical in production.

Summary

• Code examples are for reference only and need to be adjusted according to your business scenario
• Valtio's proxy-based state management is no silver bullet; choose it based on project size and tech stack.
• Understanding underlying principles is more important than memorizing APIs