react-useeffect

SKILL.md

Effects are an escape hatch from React. They let you synchronize with external systems. If there is no external system involved, you shouldn't need an Effect.

| Derived state from props/state | useState + useEffect | Calculate during render | | Expensive calculations | useEffect to cache | useMemo | | Reset state on prop change | useEffect with setState | key prop | | User event responses | useEffect watching state | Event handler directly |

| Notify parent of changes | useEffect calling onChange | Call in event handler | | Fetch data | useEffect without cleanup | useEffect with cleanup OR framework |

React useEffect 最佳實踐。在編寫效果、派生值或數據獲取時使用。教導何時不使用效果和更好的替代品，如 useMemo 或關鍵道具。 來源：nweii/agent-stuff。

查看原文