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Reactjs 在react中从firebase云firestore获取数据_Reactjs_Firebase_Google Cloud Firestore - Fatal编程技术网

Reactjs 在react中从firebase云firestore获取数据

Reactjs 在react中从firebase云firestore获取数据,reactjs,firebase,google-cloud-firestore,Reactjs,Firebase,Google Cloud Firestore,当我试图执行以下代码从firebase cloud firestore获取数据时,我得到了一个空白页 firebase.js: import firebase from "firebase"; var firebaseApp = firebase.initializeApp({ apiKey: "XXXXXXXXXXXXX", authDomain: "XXXXXXXXXXXXX", databaseURL: "

当我试图执行以下代码从firebase cloud firestore获取数据时,我得到了一个空白页

firebase.js:

import firebase from "firebase";

var firebaseApp = firebase.initializeApp({
  apiKey: "XXXXXXXXXXXXX",
  authDomain: "XXXXXXXXXXXXX",
  databaseURL: "XXXXXXXXXXXXX",
  projectId: "XXXXXXXXXXXXX",
  storageBucket: "XXXXXXXXXXXXX",
  messagingSenderId: "XXXXXXXXXXXXX",
  appId: "XXXXXXXXXXXXX"
})
var db = firebaseApp.firestore();
export { db };
从firebase cloud firestore获取数据的代码:

FormStatus.js:

import React, { Component } from "react";
import { db } from "../firebase";
class FormStatus extends Component {
    constructor(props) {
        super(props);
        this.state = { forms: [], }
    }

    componentDidMount() {
        db.collection('form').get().then(snapshot => {
            this.setState({ forms: snapshot })
        })
    }
    render() {
        const { forms } = this.state;
        return (
            <div>
                {forms.forEach(doc => {
                    return <p key={doc.id}> {doc.name}</p>
                })
                }
            </div>
        )
    }
}
export default FormStatus;
import React,{Component}来自“React”;
从“./firebase”导入{db};
类FormStatus扩展组件{
建造师(道具){
超级(道具);
this.state={forms:[],}
}
componentDidMount(){
db.collection('form').get().then(快照=>{
this.setState({forms:snapshot})
})
}
render(){
const{forms}=this.state;
返回(
{forms.forEach(doc=>{
return

{doc.name}

}) } ) } } 导出默认表单状态;

我可以在cloud firestore中发布数据,但无法从中获取数据。

。数组上的forEach
方法总是返回未定义的,使用
.map
,因此您可以获得元素数组

是的,使用
map()
代替
{forms.map(doc=>{return

{doc name}

}}}
,像这样@加亚特里帕利@Jerryc@Jerryc
未处理拒绝(TypeError):forms.map不是一个函数
我正在获取此errorconsole.log快照要查看它是什么,它需要是一个数组。映射到工作请附加您正在使用的主要对象的输出
console.log(forms)