Q431. What is the purpose of unmountComponentAtNode method?
This method is available from react-dom package and it removes a mounted React component from the DOM and clean up its event handlers and state. If no component was mount...
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Q432. What are the limitations with HOCs?
Higher-order components come with a few caveats apart from its benefits. Below are the few listed in an order, 1. **Don’t use HOCs inside the render method:** It is not r...
Q433. How to debug forwardRefs in DevTools?
**React.forwardRef** accepts a render function as parameter and DevTools uses this function to determine what to display for the ref forwarding component. For example, If...
Q434. Is it good to use arrow functions in render methods?
Yes, You can use. It is often the easiest way to pass parameters to callback functions. But you need to optimize the performance while using it. ```javascript class Foo e...
Q435. How do you say that state updates are merged?
When you call setState() in the component, React merges the object you provide into the current state. For example, let us take a facebook user with posts and comments de...
Q436. How do you pass arguments to an event handler?
During iterations or loops, it is common to pass an extra parameter to an event handler. This can be achieved through arrow functions or bind method. Let us take an examp...
Q437. How to prevent component from rendering?
You can prevent component from rendering by returning null based on specific condition. This way it can conditionally render component. ```javascript function Greeting(pr...
Q438. Give an example on How to use context?
**Context** is designed to share data that can be considered **global** for a tree of React components. For example, in the code below lets manually thread through a “the...
Q439. How do you use contextType?
ContextType is used to consume the context object. The contextType property can be used in two ways, 1. **contextType as property of class:** The contextType property on ...
Q440. What is a consumer?
A Consumer is a React component that subscribes to context changes. It requires a function as a child which receives current context value as argument and returns a react...