Q2401. 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...
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Q2402. 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...
Q2403. 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...
Q2404. 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 ...
Q2405. 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...
Q2406. What is the difference between `super()` and `super(props)` in React using ES6 classes?
When you want to access `this.props` in `constructor()` then you should pass props to `super()` method. **Using `super(props)`:** ```javascript class MyComponent extends ...
Q2407. How do you implement zero timeout in modern browsers?
You can't use setTimeout(fn, 0) to execute the code immediately due to minimum delay of greater than 0ms. But you can use window.postMessage() to achieve this behavior.
Q2408. What is the difference between `setState()` and `replaceState()` methods?
When you use `setState()` the current and previous states are merged. `replaceState()` throws out the current state, and replaces it with only what you provide. Usually `...
Q2409. What are tasks in event loop?
A task is any javascript code/program which is scheduled to be run by the standard mechanisms such as initially starting to run a program, run an event callback, or an in...
Q2410. How to listen to state changes?
The `componentDidUpdate` lifecycle method will be called when state changes. You can compare provided state and props values with current state and props to determine if ...