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Lære Adding Methods to Classes | ES6 Class Fundamentals
JavaScript Classes and OOP Foundations

bookAdding Methods to Classes

When you define a method inside a JavaScript class, you are creating an instance method. This means every object created from that class will have access to the method, but the method itself is shared by all instances rather than being duplicated for each one. Defining methods in the class body (outside the constructor) attaches them to the class's prototype. This makes your code more efficient, since only one copy of the method exists in memory, regardless of how many objects you create from the class.

To add a method, simply write its name followed by parentheses and a code block within the class definition—there is no need for the function keyword. These methods can access the instance's properties using the this keyword.

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class Person { constructor(name) { this.name = name; } greet() { return "Hello, my name is " + this.name + "!"; } } const alice = new Person("Alice"); console.log(alice.greet()); // Output: Hello, my name is Alice!
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Which of the following statements best describes the difference between an instance method and an instance property in a JavaScript class?

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bookAdding Methods to Classes

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When you define a method inside a JavaScript class, you are creating an instance method. This means every object created from that class will have access to the method, but the method itself is shared by all instances rather than being duplicated for each one. Defining methods in the class body (outside the constructor) attaches them to the class's prototype. This makes your code more efficient, since only one copy of the method exists in memory, regardless of how many objects you create from the class.

To add a method, simply write its name followed by parentheses and a code block within the class definition—there is no need for the function keyword. These methods can access the instance's properties using the this keyword.

123456789101112
class Person { constructor(name) { this.name = name; } greet() { return "Hello, my name is " + this.name + "!"; } } const alice = new Person("Alice"); console.log(alice.greet()); // Output: Hello, my name is Alice!
copy
question mark

Which of the following statements best describes the difference between an instance method and an instance property in a JavaScript class?

Select the correct answer

Var alt klart?

Hvordan kan vi forbedre det?

Tak for dine kommentarer!

Sektion 1. Kapitel 5
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