我如何使用 React 从 firebase 9 读取数组

How can i read an array from firebase 9 using react

我想读取 firebase 中的数组 火力阵列格式: enter image description here

并将其存储在类似于 Chart_data 我想要这种格式 enter image description here

此代码是我通常在 Firestore 中执行的代码。我不知道您在数据库中使用的是什么存储结构,但我假设您有一组用户,然后是一组图表。

如果不是,就相应地调整它。

进口:

import React, { useEffect, useState } from "react";
import { doc, getDoc } from "firebase/firestore";
import { db } from "../../../../../firebaseConfig"; // path to your firebaseConfig file

代码,粘贴到功能组件中

    const [chartData, setChartData] = useState([]);

    // a reference to the chart you want
    const chartReference = doc(db, "dashboard_analytics", "E8V0JbotwbK9TqgtMSXF");

    // used to fetch the data from your firestore database
    const fetchChartData = async () => {
        // attempts to fetch data for the referenced chart
        const documentSnapshot = await getDoc(chartReference);

        let docChartData = [];

        if (docSnap.exists()) {
            // the name of the field of the array
            docChartData = docSnap.data().ordersGraph;
        } else {
            // The document doesn't exist
            console.log("No such document!");
        }

        // stores ordersGraph array into the state variable, chartData
        setChartData([...docChartData]);
    };

    useEffect(() => {
        // calls the function on the load of the page
        fetchChartData();
    }, []);

然后您可以使用 chartData 状态变量访问它。