BitWithBite
React · Quick Reference
Lesson 9 — useReducer Cheat Sheet
In one line: useReducer centralises related state updates into one function instead of scattering setState calls.
Structure
1const [state,dispatch]=useReducer(reducer,init);
2reducer(state,action) — switch on action.type.
3dispatch({type:"ADD",item:{...}});
When to Prefer
Multiple related updates
Use useReducer
Next state depends on previous non-trivially
Use useReducer
Simple independent values
Use useState