javascript - how to wait for foreach in firebase data retrive process

Question

This question already has answers here: question from:https://stackoverflow.com/questions/65897367/how-to-wait-for-foreach-in-firebase-data-retrive-process

Answer 1

The issue is not async/await, your res is a Promise, and the length will always be undefined. For example:

var p = Promise.resolve([1,2,3]);
console.log(p.length) // undefined