What are the differences between async and sync route guards in Vue Router?

What are the differences between async and sync route guards in Vue Router?

In Vue Router, sync route guards execute immediately and block navigation until they finish, while async guards return a promise and allow navigation to proceed once the promise resolves.

Can you give me an example of each type of guard?

Sure! A sync guard might look like this: beforeEnter: (to, from, next) => { if (isAuthenticated) next(); else next('/login'); }. An async guard could be: beforeEnter: (to, from, next) => { fetchUserData().then(user => { if (user) next(); else next('/login'); }); }.

When should I use async guards over sync guards?

Use async guards when you need to perform asynchronous operations, like fetching data or checking permissions, before allowing navigation.

Are there any performance implications of using async guards?

Yes, async guards can introduce a delay in navigation since they wait for the promise to resolve. It's important to manage user experience during this wait.