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The entries() method of the JavaScript Object object is a powerful tool introduced in ES2017. It allows you to retrieve all the own properties of an object and returns them as an array of [key, value] pairs. Usage To understand how to use the entries() method, let’s consider a simple example. Suppose we have an object called person with the properties name and age: const person = { name: 'Fred', age: 87 } We can use the entries() method on the person object to retrieve an array containing all its properties:...

The isFrozen() method in JavaScript can be used to determine whether an object is frozen or not. When an object is frozen, it means that it cannot be modified. This method accepts an object as an argument and returns true if the object is frozen, and false otherwise. Objects are typically frozen using the Object.freeze() function. When an object is frozen, its properties cannot be added, modified, or removed. The isFrozen() method allows you to check the frozen state of an object and make decisions based on that information....

Learn all about the setPrototypeOf() method in the JavaScript Object object. Setting the prototype of an object is made possible with the setPrototypeOf() method. To dive deeper into JavaScript Prototypal Inheritance, check out my comprehensive guide here. Syntax: Object.setPrototypeOf(object, prototype) Example: const Animal = {} Animal.isAnimal = true const Mammal = Object.create(Animal) Mammal.isMammal = true console.log('-------') Mammal.isAnimal // true const dog = Object.create(Animal) dog.isAnimal // true console.log(dog.isMammal) // undefined Object.setPrototypeOf(dog, Mammal) console....

The getOwnPropertyDescriptors() method of the Object object in JavaScript allows us to retrieve all own (non-inherited) property descriptors of an object. By using this method, we can obtain a new object that provides a comprehensive list of descriptors. Here’s an example to illustrate its usage: const dog = {} Object.defineProperties(dog, { breed: { value: 'Siberian Husky' } }) Object.getOwnPropertyDescriptors(dog) /* { breed: { value: 'Siberian Husky', writable: false, enumerable: false, configurable: false } } */ One key use case for this method arises from the limitations of Object....

When working with Vue, you might find yourself asking the question, “Why must data be a function that returns an object, instead of just an object?” Consider the following example: <template> <a v-on:click="counter = counter + 1">{{counter}}</a> </template> <script> export default { data: function() { return { counter: 0 } } } </script> You may have also noticed that in some places, data is not a function, such as in the App component in various examples....

Learn two modern techniques for working with arrays and objects in JavaScript. You can expand an array, object, or string using the spread operator .... Let’s start with an example for arrays: const a = [1, 2, 3]; To create a new array, you can use: const b = [...a, 4, 5, 6]; You can also create a copy of an array using: const c = [...a]; This also works for objects....