Q2381. How do you verify that an argument is a Number or not?
The combination of IsNaN and isFinite methods are used to confirm whether an argument is a number or not. ```javascript function isNumber(n) { return !isNaN(parseFloat(n)...
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Q2382. How you use decorators in React?
You can _decorate_ your _class_ components, which is the same as passing the component into a function. **Decorators** are flexible and readable way of modifying componen...
Q2383. How do you create copy to clipboard button?
You need to select the content(using .select() method) of the input element and execute the copy command with execCommand (i.e, execCommand('copy')). You can also execute...
Q2384. What is CRA and its benefits?
**⚠️ OUTDATED:** Create React App (CRA) is no longer actively maintained and is not recommended for new projects as of 2024+. **Modern Alternatives:** Use **Vite** (for S...
Q2385. What is the shortcut to get timestamp?
You can use `new Date().getTime()` to get the current timestamp. There is an alternative shortcut to get the value. ```javascript console.log(+new Date()); console.log(Da...
Q2386. What is the lifecycle methods order in mounting?
The lifecycle methods are called in the following order when an instance of a component is being created and inserted into the DOM. 1. `constructor()` 2. `static getDeriv...
Q2387. How do you flattening multi dimensional arrays?
Flattening bi-dimensional arrays is trivial with Spread operator. ```javascript const biDimensionalArr = [11, [22, 33], [44, 55], [66, 77], 88, 99]; const flattenArr = []...
Q2388. What are the lifecycle methods going to be deprecated in React v16?
**⚠️ FULLY DEPRECATED:** These lifecycle methods have been deprecated and removed from React 17+. The following lifecycle methods were deprecated due to unsafe coding pra...
Q2389. What is the easiest multi condition checking?
You can use `indexOf` to compare input with multiple values instead of checking each value as one condition. ```javascript // Verbose approach if ( input === "first" || i...
Q2390. What is the purpose of `getDerivedStateFromProps()` lifecycle method?
The new static `getDerivedStateFromProps()` lifecycle method is invoked after a component is instantiated as well as before it is re-rendered. It can return an object to ...