我正在从我的 nodejs 获取动态数据到 reactjs 但我收到一条错误消息 "POST IS NOT DEFINED"

Question

我已经使用节点在我的 mongodb 数据库中创建了条目，现在我正在尝试从后端获取该数据以对前端做出反应，用于节点中跨平台的第 3 方应用程序是 cors 和react 是 axios（在脚本中我添加了“proxy”：“http://localhost:5000”（5000 是我的后端端口）

这是我的 NovelCard.js

代码

import React, { Component } from 'react';
import { Container } from 'react-bootstrap';
import Card from 'react-bootstrap/Card';

import axios from 'axios';

const createSet = (post) => {
  <Card style={{ width: '18rem' }}>
    <Card.Img variant="top" src="holder.js/100px180" />
    <Card.Body>
      <Card.Title>{post.name}</Card.Title>
      <Card.Subtitle className="mb-2 text-muted">{post.author}</Card.Subtitle>
      <Card.Text>{post.synopsis}</Card.Text>
    </Card.Body>
  </Card>;
};

class Latest extends Component {
  state = {
    name: '',
    author: '',
    synopsis: '',
    post: [],
  };

  componentDidMount = () => {
    this.getData();
  };

  getData = () => {
    axios
      .get('http://localhost:5000/novels/')
      .then((res) => {
        const data = res.data;
        this.setState({ post: data });
        console.log('data recived');
      })
      .catch(() => {
        alert('error');
      });
  };


  render() {
    console.log('state', this.state);
    return <Container>{post.map(createSet)}</Container>;
  }
}
export default Latest;

我收到错误提示 ***

src\components\home\Latest\NovelCard.js Line 45:24: 'post' is not defined no-undef

Answer 1

您的 post 变量在您所在的州可用。您需要在 render 函数中执行类似的操作。

render() {
  console.log('state', this.state);
  return <Container>{this.state.post.map(createSet)}</Container>;
}

或者你也可以这样做。

render() {
  const { post } = this.state;
  console.log('state', this.state);
  return <Container>{post.map(createSet)}</Container>;
}

我正在从我的 nodejs 获取动态数据到 reactjs 但我收到一条错误消息 "POST IS NOT DEFINED"

I'm fetching dynamic data from my nodejs to reactjs but I get an error saying "POST IS NOT DEFINED"

mongodb

node.js

reactjs

mern