How to use ref.once with Firebase 9?-CodePudding

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How is this meant to be updated for Firebase 9.x? The Firebase 9 docs don't seem to offer any example.

CodePudding user response：

firebaser here

The once('value' method has been replace by a get() function, so:

const snapshot = await get(ref);

Also see the Firebase documentation on reading data once.

To unsubscribe from a realtime listener (so not get()) you now can use the return value from the function you called to subscribe.

So if you subscribe with:

const unsubscribe = onValue(ref, (snapshot) => { ... });

You can then later unsubscribe with:

unsubscribe();

This is what the Firestore SDKs already did, and feedback indicated that devs preferred that over off.