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

Constructor functions are used to create objects with shared properties and methods by defining those properties and methods on the constructor's prototype property. Objects created with the constructor inherit these properties and methods through the prototype chain.

Before modern ES6 classes, Constructor Functions were the standard way to create multiple objects of the same 'type.' They act like a blueprint, allowing you to stamp out new objects with the same structure.

If you put a method inside the constructor function (like this.sayHi = function() {...}), every single object you create will carry its own copy of that function. If you have 1,000 users, you have 1,000 identical functions eating up memory. Instead, we attach shared methods to the function's .prototype.