Question

我正在尝试为从forEach循环外部声明的变量设置值，但我得到此警告：标识符'arr'从未重新分配；使用'const'代替'let'.tslint（prefer-const）...当我部署代码时，我只会得到一个空变量

import * as functions from "firebase-functions"
import * as admin from "firebase-admin"

admin.initializeApp()

export const test = functions.https.onRequest(async (req, res) => {

    const stores = await admin.firestore().collection('stores').get()

    let arr: boolean[] = []

    // tslint:disable-next-line: no-void-expression
    await stores.forEach(async (store) => {
        const sales = await store.ref.collection('sales').get()
        arr.push(sales.empty)
    })

    console.log(arr);

    res.status(200).send({
    arr: arr
    })
})

Answer 1

使用以下代码获得了预期的结果：

export const test = functions.https.onRequest(async (req, res) => {

    const fetchStores = await admin.firestore().collection('stores').get()
    const arr = []

    for (const store of fetchStores.docs) {
        const sales = await store.ref.collection('sales').get()
        arr.push(sales.empty)
    }

    res.status(200).send({arr: arr})

})

如何在forEach循环中访问外部变量

1 个答案: