Q2341. What is the output of below function calls?
**Code snippet:** ```javascript const circle = { radius: 20, diameter() { return this.radius * 2; }, perimeter: () => 2 * Math.PI * this?.radius, }; ``` ```javascript con...
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Q2342. How to bind methods or event handlers in JSX callbacks?
There are 3 possible ways to achieve this in class components: 1. **Binding in Constructor:** In JavaScript classes, the methods are not bound by default. The same rule a...
Q2343. How to remove all line breaks from a string?
The easiest approach is using regular expressions to detect and replace newlines in the string. In this case, we use replace function along with string to replace with, w...
Q2344. How to pass a parameter to an event handler or callback?
You can use an _arrow function_ to wrap around an _event handler_ and pass parameters: ```jsx harmony this.handleClick(id)} /> ``` This is an equivalent to calling `.bind...
Q2345. What is the difference between reflow and repaint?
A _repaint_ occurs when changes are made which affect the visibility of an element, but not its layout. Examples of this include outline, visibility, or background color....
Q2346. What is the use of refs?
The _ref_ is used to return a reference to the element. They _should be avoided_ in most cases, however, they can be useful when you need a direct access to the DOM eleme...
Q2347. What happens with negating an array?
Negating an array with `!` character will coerce the array into a boolean. Since Arrays are considered to be truthy So negating it will return `false`. ```javascript cons...
Q2348. How to create refs?
There are two approaches 1. This is a recently added approach. _Refs_ are created using `React.createRef()` method and attached to React elements via the `ref` attribute....
Q2349. What happens if we add two arrays?
If you add two arrays together, it will convert them both to strings and concatenate them. For example, the result of adding arrays would be as below, ```javascript conso...
Q2350. What are forward refs?
_Ref forwarding_ is a feature that lets some components take a _ref_ they receive, and pass it further down to a child. ```jsx harmony const ButtonElement = React.forward...