Q1001. What are wrapper objects?
Primitive Values like string,number and boolean don't have properties and methods but they are temporarily converted or coerced to an object(Wrapper object) when you try ...
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Q1002. What is the recommended ordering of methods in component class?
_Recommended_ ordering of methods from _mounting_ to _render stage_: 1. `static` methods 2. `constructor()` 3. `getChildContext()` 4. `componentWillMount()` 5. `component...
Q1003. What is AJAX?
AJAX stands for Asynchronous JavaScript and XML and it is a group of related technologies(HTML, CSS, JavaScript, XMLHttpRequest API etc) used to display data asynchronous...
Q1004. Why we need to pass a function to setState()?
The reason behind for this is that `setState()` is an asynchronous operation. React batches state changes for performance reasons, so the state may not change immediately...
Q1005. Why is `isMounted()` an anti-pattern and what is the proper solution?
The primary use case for `isMounted()` is to avoid calling `setState()` after a component has been unmounted, because it will emit a warning. ```javascript if (this.isMou...
Q1006. How to cancel a fetch request?
Until a few days back, One shortcoming of native promises is no direct way to cancel a fetch request. But the new `AbortController` from js specification allows you to us...
Q1007. What is the difference between constructor and getInitialState?
You should initialize state in the constructor when using ES6 classes, and `getInitialState()` method when using `React.createClass()`. **Using ES6 classes:** ```javascri...
Q1008. What is web speech API?
Web speech API is used to enable modern browsers recognize and synthesize speech(i.e, voice data into web apps). This API was introduced by W3C Community in the year 2012...
Q1009. Can you force a component to re-render without calling setState?
By default, when your component's state or props change, your component will re-render. If your `render()` method depends on some other data, you can tell React that the ...
Q1010. What is minimum timeout throttling?
Both browser and NodeJS javascript environments throttles with a minimum delay that is greater than 0ms. That means even though setting a delay of 0ms will not happen ins...