Spread props in Svelte - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does {...props} do in a Svelte component?

It takes all properties from the props object and passes them as individual attributes to a component or element.

beginner

How do you use spread props to pass multiple attributes to an HTML element in Svelte?

You create an object with the attributes and then use {...object} inside the element tag to apply all attributes at once.

intermediate

Can you override a spread prop by specifying the same attribute after the spread in Svelte?

Yes. Attributes specified after the spread will override those from the spread object.

beginner

Why use spread props instead of listing each prop individually in Svelte?

It saves time and keeps code clean when passing many props, especially if they come from an object.

intermediate

What happens if you spread an object with undefined or null values in Svelte props?

Undefined or null values are omitted; the corresponding attributes are not rendered.

In Svelte, how do you pass all properties from an object props to a component?

A <Component (props) />

B <Component [props] />

C <Component {...props} />

D <Component props />

Using {...props} spreads all properties as individual attributes.

If you write <button {...attrs} disabled> in Svelte, what happens to the disabled attribute?

A It causes an error

B The button is disabled regardless of <code>attrs</code>

C The button is not disabled

D The disabled attribute from <code>attrs</code> overrides the explicit disabled

Explicit attributes after the spread override the spread props, so disabled is set.

Which of these is a benefit of using spread props in Svelte?

A Passing many props quickly and cleanly

B Making components slower

C Preventing props from being passed

D Automatically validating props

Spread props help pass many props quickly and keep code clean.

What happens if you spread an object with a property set to undefined in Svelte?

A The attribute is ignored

B An error is thrown

C The attribute is passed with no value

D The attribute is set to 'undefined' string

Undefined values are ignored; the attribute is not rendered.

Can you use spread props on native HTML elements in Svelte?

A No, only on components

B Only on custom elements

C Only on <div> elements

D Yes, to pass multiple attributes at once

Spread props work on any element to pass multiple attributes quickly.

Explain how spread props work in Svelte and why they are useful.

Think about how you pass many settings to a component or element at once.

Describe a scenario where spread props can help simplify your Svelte code.

Imagine you have a settings object with many keys to pass to a button or input.