使用异步/等待在firebase中运行查询 [英] running queries in firebase using async / await

问题描述

感谢Firebase 添加了对诺言的支持，是否可以在async函数内部运行类似以下查询的方法?:

Appreciating that firebase has added support for promises, is there a way to run a query like the following inside of an async function?:

const eventref = this.db.ref('cats/whiskers');
const value = await eventref.once('value')

运行以上命令返回对value的承诺，我希望获取存储在cats/whiskers的json blob.

Running the above returns a promise for value, I'm hoping to get the json blob that is stored at cats/whiskers.

推荐答案

value的结果是快照，我们还需要执行1步来获取值.这应该像:

The result of value is a snapshot, we need 1 more step to get the value. This should be like:

const eventref = this.db.ref('cats/whiskers');
const snapshot = await eventref.once('value');
const value = snapshot.val();

这篇关于使用异步/等待在firebase中运行查询的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！