What is the `instanceof` operator in JavaScript?

Description : `instanceof` checks whether an object is an instance of a specific class or constructor.

Answer :

`instanceof` is an operator in JavaScript that checks whether an object is an instance of a specific class or constructor function. It returns `true` if the object is an instance of the class or constructor, and `false` otherwise. This operator is useful for checking the prototype chain and determining if an object inherits from a particular class or constructor. 

function Person(name) {
  this.name = name;
}

const alice = new Person('Alice');
console.log(alice instanceof Person); // true
console.log(alice instanceof Object); // true
console.log(alice instanceof Array); // false

`instanceof` is an operator in JavaScript that checks whether an object is an instance of a specific class or constructor function. It returns `true` if the object is an instance of the class or constructor, and `false` otherwise. This operator is useful for checking the prototype chain and determining if an object inherits from a particular class or constructor. 

function Person(name) {
  this.name = name;
}

const alice = new Person('Alice');
console.log(alice instanceof Person); // true
console.log(alice instanceof Object); // true
console.log(alice instanceof Array); // false

Category : Javascript

Created Date : 9/6/2024

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What is the `String.prototype.anchor` method in JavaScript?

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2024-09-06 last updatedFreeJavascript

`String.prototype.anchor` creates an HTML `<a>` element wrapping the string with a specified name attribute. This method is deprecated and should not be used in modern applications. 

const str = 'Click here';
const anchoredStr = str.anchor('top');
console.log(anchoredStr); // '<a name="top">Click here</a>'

`String.prototype.anchor` creates an HTML `<a>` element wrapping the string with a specified name attribute. This method is deprecated and should not be used in modern applications. 

const str = 'Click here';
const anchoredStr = str.anchor('top');
console.log(anchoredStr); // '<a name="top">Click here</a>'

`String.prototype.anchor` creates an HTML `<a>` element wrapping the string with a specified name attribute. This method is deprecated and should not be used in modern applications. 

const str = 'Click here';
const anchoredStr = str.anchor('top');
console.log(anchoredStr); // '<a name="top">Click here</a>'

`String.prototype.anchor` creates an HTML `<a>` element wrapping the string with a specified name attribute. This method is deprecated and should not be used in modern applications. 

const str = 'Click here';
const anchoredStr = str.anchor('top');
console.log(anchoredStr); // '<a name="top">Click here</a>'

What is the `String.prototype.small` method in JavaScript?

What is the `String.prototype.small` method in JavaScript?

More details

2024-09-06 last updatedFreeJavascript

`String.prototype.small` returns a string wrapped in HTML `<small>` tags. This method is deprecated and should not be used in modern applications. 

const str = 'hello';
const smallStr = str.small();
console.log(smallStr); // '<small>hello</small>'

`String.prototype.small` returns a string wrapped in HTML `<small>` tags. This method is deprecated and should not be used in modern applications. 

const str = 'hello';
const smallStr = str.small();
console.log(smallStr); // '<small>hello</small>'

`String.prototype.small` returns a string wrapped in HTML `<small>` tags. This method is deprecated and should not be used in modern applications. 

const str = 'hello';
const smallStr = str.small();
console.log(smallStr); // '<small>hello</small>'

`String.prototype.small` returns a string wrapped in HTML `<small>` tags. This method is deprecated and should not be used in modern applications. 

const str = 'hello';
const smallStr = str.small();
console.log(smallStr); // '<small>hello</small>'