Questions

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1What is the constructor function?

2What are Objects?

3What are the properties of an object?

4How does javascript implements object oriented programming?

5What are the key differences between javascript’s Object-based Inheritance and Conventional Class-based Inheritance?

6What is a prototype in JavaScript?

7How we can implement prototype-based inheritance?

8Explain the prototype chain and its role in property lookup.

9What is the difference between an object's `__proto__` and a constructor function's `prototype` property and [[Prototype]]?

10What are object wrappers for primitive type?

11Can you explain the use of object wrappers with examples?

12Explain how the `instanceof` operator works.

13What are different methods to create an object?

14What is an object initializer?

15What does the `Object.create()` method do?

16How are constructor functions used to create objects with shared properties and methods?

17Show an example of ES6 classes to create objects and inherit properties?

18What are factory functions in JavaScript ?

19What are Object constructors in JavaScript ?

20How can you add new properties and methods to the prototype of an existing constructor function?

21What is prototype pollution, and how can it be a security risk in JavaScript?

22Is modifying or extending built-in object prototypes recommended (e.g., adding a method to `Array.prototype`)? Why or why not?

23What happens when you try to access a property that doesn't exist on an object?

24How can you prevent or mitigate prototype pollution vulnerabilities in your code?

25How does the `Object.prototype.hasOwnProperty()` method work?

26How can you optimize prototype chain lookup for better performance?

27Can you explain how `Object.prototype.constructor` property works?

28What is the difference between modifying the prototype of an object and adding a property directly to the object?

29How does JavaScript handle circular references in object prototypes?

30What is static dispatching in object-oriented programming?

31What is the purpose of the `Object.keys()` method?

32Write a function flattenObject(obj) that flattens a deeply nested object into a single-level object, using dot notation for nested keys.

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Explain how the `instanceof` operator works.

The instanceof operator checks whether an object is an instance of a particular constructor function or class. It traverses the prototype chain of the object, looking for a match with the prototype of the constructor function.

It checks if a specific constructor's prototype exists anywhere in that object's prototype chain.

javascript

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Even though strings have Object Wrappers, literal primitives are not considered instances of their constructors