Q401. How do you get enumerable key and value pairs?
The `Object.entries()` method is used to return an array of a given object's own enumerable string-keyed property [key, value] pairs, in the same order as that provided b...
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Q402. What are the rules covered by diffing algorithm?
When diffing two trees, React first compares the two root elements. The behavior is different depending on the types of the root elements. It covers the below rules durin...
Q403. What is the main difference between Object.values and Object.entries method?
The `Object.values()` method's behavior is similar to `Object.entries()` method but it returns an array of values instead [key,value] pairs. ```javascript const object = ...
Q404. When do you need to use refs?
There are few use cases to go for refs, 1. Managing focus, text selection, or media playback. 2. Triggering imperative animations. 3. Integrating with third-party DOM lib...
Q405. How can you get the list of keys of any object?
You can use the `Object.keys()` method which is used to return an array of a given object's own property names, in the same order as we get with a normal loop. For exampl...
Q406. Must prop be named as render for render props?
Even though the pattern named render props, you don’t have to use a prop named render to use this pattern. i.e, Any prop that is a function that a component uses to know ...
Q407. How do you create an object with a prototype?
The `Object.create()` method is used to create a new object with the specified prototype object and properties. i.e, It uses an existing object as the prototype of the ne...
Q408. What are the problems of using render props with pure components?
If you create a function inside a render method, it negates the purpose of pure component. Because the shallow prop comparison will always return false for new props, and...
Q409. What is a WeakSet?
A `WeakSet` is used to store a collection of weakly(weak references) held objects. The syntax would be as follows, ```javascript new WeakSet([iterable]); ``` Let's see th...
Q410. What is windowing technique?
Windowing is a technique that only renders a small subset of your rows at any given time, and can dramatically reduce the time it takes to re-render the components as wel...