Why lifecycle hooks run code at key moments in Svelte - Quick Recap

Recall & Review

beginner

What is a lifecycle hook in Svelte?

A lifecycle hook is a special function that runs code at important times during a component's life, like when it starts, updates, or stops.

beginner

Why do we use the onMount lifecycle hook?

onMount runs code right after the component appears on the screen. It's useful for starting tasks like fetching data or setting up timers.

intermediate

What does the beforeUpdate hook do?

beforeUpdate runs code just before the component updates its content on the screen. It helps prepare or check things before the change happens.

intermediate

How does the onDestroy hook help with cleanup?

onDestroy runs code when the component is removed from the screen. It helps stop timers, remove event listeners, or free resources to keep the app fast and clean.

beginner

Why is it important to run code at key moments in a component's life?

Running code at key moments helps the app stay organized, efficient, and responsive. It makes sure things start, update, and stop at the right time, like a well-timed dance.

Which Svelte lifecycle hook runs code right after the component appears on the screen?

A onMount

B beforeUpdate

C afterUpdate

D onDestroy

onMount runs code after the component is added to the page.

What is the main purpose of the onDestroy hook?

A Start timers

B Fetch data

C Clean up resources

D Update the UI

onDestroy helps clean up things like timers and event listeners when the component is removed.

When does the beforeUpdate hook run?

A After the component is removed

B Before the component updates

C When the component mounts

D After the component updates

beforeUpdate runs just before the component changes on the screen.

Why are lifecycle hooks useful in Svelte components?

A To handle user input only

B To write CSS styles

C To create new components

D To run code at important times in the component's life

Lifecycle hooks let you run code exactly when the component starts, updates, or stops.

Which hook would you use to fetch data when a component first appears?

A onMount

B beforeUpdate

C afterUpdate

D onDestroy

onMount is the right place to start tasks like fetching data when the component loads.

Explain why lifecycle hooks are important in Svelte components and give examples of when you might use them.

Think about what happens when a component starts, changes, or stops.

Describe the difference between beforeUpdate and afterUpdate hooks in Svelte.

Consider when you want to prepare for or respond to updates.