Learn JavaScript from Scratch JavaScript for Everyone - JavaScript Classes

The video tutorial introduces JavaScript classes, explaining their syntax, advantages, and usage. It covers how classes are similar to objects but offer more advanced features like subclassing and method reuse. The tutorial demonstrates class instantiation, method implementation, and handling undefined properties with default values. It emphasizes the importance of classes in modern JavaScript and their resemblance to classes in other OOP languages like Python and PHP.

What is one of the main benefits of using classes in JavaScript?

• They allow for procedural programming.

• They enable subclassing and method inheritance.

• They make JavaScript code run faster.

• They eliminate the need for functions.

Which keyword is used to define a class in JavaScript?

• function

• class

• method

• object

What is the correct way to instantiate a class in JavaScript?

• var obj = myClass();

• let obj = new myClass();

• const obj = create myClass();

• obj = myClass.new();

What does the 'this' keyword refer to inside a class method?

• The global object

• The class itself

• A local variable

• The current instance of the class

How can you set a default value for a property in a class if it is undefined?

• Using an if statement to check for undefined

• Using a try-catch block

• Using a switch statement

• Using a for loop

What happens if you try to access a property that hasn't been set in a class?

• It returns null

• It throws an error

• It returns an empty string

• It returns undefined

Which of the following is a method of a class in JavaScript?

• document.write

• console.log

• setname

• alert