Introduction to JavaScript Functions

The main logic of the QR code generator application can be written in the form of functions using JavaScript. This defines logic for actions like getting input from the user, generating and downloading the QR code in the application. Let’s look into necessary functions we used in this application.

onChange()

• It allows you to handle changes to input elements (like text fields, checkboxes, etc.) in a component.
• It's used to capture user input and update the component's state accordingly.
• Syntax:

<input type="text" value={value} onChange={handleChange} />

onClick()

• It allows you to handle click events on elements (like buttons).
• It's used to trigger actions when the user clicks a button or other clickable element.
• Syntax:

<button onClick={handleClick}>Click Me</button>

useState()

• It allows you to add state to functional components.
• It's used to store and update dynamic values in the component.
• Syntax:

const [state, setState] = useState(initialValue);

In the next module, we will get into the actual implementation and styling of the application.