Lecture 07 (reacts)

What is React?

• A database system

• A JavaScript library for building user interfaces

• A programming language

• A backend framework

What is a key feature of React?

• Direct DOM manipulation

• SQL integration

• Virtual DOM

• File storage system

What does the Virtual DOM do?

• Deletes HTML elements

• Updates the whole DOM every time

• Updates only the changed parts of the DOM

• Stores data permanently

React components can be described as:

• Only HTML elements

• Database tables

• CSS styles

• Reusable building blocks for UI

What are the inputs to a React component?

• HTML and CSS

• Props and State

• Functions only

• Variables only

What is the difference between state and props?

• Props can be changed, state cannot

• State is read-only, props are editable

• Props are read-only, state can change

• No difference

Which method is used to update state in a React class component?

• this.updateState()

• this.changeState()

• this.setState()

• this.modifyState()

In ES6, which keyword has block scope?

• var

• class

• function

• let

What is an arrow function in ES6?

• A way to create arrays

• A shorter syntax for writing functions

• A method for styling components

• A database query

What is the purpose of props in React?

• To store internal component data

• To pass data from one component to another

• To update the DOM directly

• To style components