Svelte · Middle · Question 58 of 75

What does `$props.id()` (Svelte 5.20+) generate?

<script>
  const uid = $props.id();
</script>

<label for="{uid}-email">Email</label>
<input id="{uid}-email" />

✓Correct answer: An id unique to the component instance that is the same during SSR and hydration, handy for linking labels and ARIA attributes
2The id of the parent component
3A random id that changes on every render

Explanation

Random ids generated with Math.random() would differ between server and client and break hydration.

Further reading

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