Q261. What is React hydration?
React hydration is used to add client-side JavaScript interactivity to pre-rendered static HTML generated by the server. It is used only for server-side rendering(SSR) to...
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Q262. How do you update objects inside state?
You cannot update the objects which exists in the state directly. Instead, you should create a fresh new object (or copy from the existing object) and update the latest s...
Q263. How do you update nested objects inside state?
You cannot simply use spread syntax for all kinds of objects inside state. Because spread syntax is shallow and it copies properties for one level deep only. If the objec...
Q264. How do you update arrays inside state?
Eventhough arrays in JavaScript are mutable in nature, you need to treat them as immutable while storing them in a state. That means, similar to objects, the arrays canno...
Q265. How do you use immer library for state updates?
Immer library enforces the immutability of state based on **copy-on-write** mechanism. It uses JavaScript proxy to keep track of updates to immutable states. Immer has 3 ...
Q266. What are the benefits of preventing the direct state mutations?
In React and modern JavaScript state management, **immutability** (preventing direct mutation of state objects and arrays) is a core foundational architectural requiremen...
Q267. What are the preferred and non-preferred array operations for updating the state?
The below table represent preferred and non-preferred array operations for updating the component state. | Action | Preferred | Non-preferred | | --------- | ------------...
Q268. What will happen by defining nested function components?
Technically it is possible to write nested function components but it is not suggested to write nested function definitions. Because it leads to unexpected bugs and perfo...
Q269. Can I use keys for non-list items?
Keys are primarily used for rendering list items but they are not just for list items. You can also use them React to distinguish components. By default, React uses order...
Q270. What are the guidelines to be followed for writing reducers?
There are two guidelines to be taken care while writing reducers in your code. 1. Reducers must be pure without mutating the state. That means, same input always returns ...