Question

我正在跟踪在线MERN锻炼追踪器的示例项目。后端完全正常运行，所有原始操作均成功运行。编辑或更新数据时，前端React部分不起作用。本质上，我更新数据的唯一方法是使用POSTMAN。我已经尝试配置所有内容，据我了解，Axios请求无法正常工作。

我已附加了与编辑或更新功能相关的所有代码

-----快速导航到第一部分代码中的运动部分的相关部分。并第二次看了组件的数量和提交方法----------

import React, { Component } from 'react';
import { Link } from 'react-router-dom';
import axios from 'axios';

const Exercise = props => (
  <tr>
    <td>{props.exercise.username}</td>
    <td>{props.exercise.description}</td>
    <td>{props.exercise.duration}</td>
    <td>{props.exercise.date.substring(0,10)}</td>
    <td>
      <Link to={"/edit/"+props.exercise._id}>edit</Link> | <a href="#" onClick={() => { props.deleteExercise(props.exercise._id) }}>delete</a>
    </td>
  </tr>
)

export default class ExercisesList extends Component {
  constructor(props) {
    super(props);

    this.deleteExercise = this.deleteExercise.bind(this)

    this.state = {exercises: []};
  }

  componentDidMount() {
    axios.get('http://localhost:5000/exercises/')
      .then(response => {
        this.setState({ exercises: response.data })
      })
      .catch((error) => {
        console.log(error);
      })
  }

  deleteExercise(id) {
    axios.delete('http://localhost:5000/exercises/'+id)
      .then(response => { console.log(response.data)});

    this.setState({
      exercises: this.state.exercises.filter(el => el._id !== id)
    })
  }

  exerciseList() {
    return this.state.exercises.map(currentexercise => {
      return <Exercise exercise={currentexercise} deleteExercise={this.deleteExercise} key={currentexercise._id}/>;
    })
  }

  render() {
    return (
      <div>
        <h3>Logged Exercises</h3>
        <table className="table">
          <thead className="thead-light">
            <tr>
              <th>Username</th>
              <th>Description</th>
              <th>Duration</th>
              <th>Date</th>
              <th>Actions</th>
            </tr>
          </thead>
          <tbody>
            { this.exerciseList() }
          </tbody>
        </table>
      </div>
    )
  }
}

import React, { Component } from 'react';
import axios from 'axios';
import DatePicker from 'react-datepicker';
import "react-datepicker/dist/react-datepicker.css";

export default class EditExercise extends Component {
  constructor(props) {
    super(props);

    this.onChangeUsername = this.onChangeUsername.bind(this);
    this.onChangeDescription = this.onChangeDescription.bind(this);
    this.onChangeDuration = this.onChangeDuration.bind(this);
    this.onChangeDate = this.onChangeDate.bind(this);
    this.onSubmit = this.onSubmit.bind(this);

    this.state = {
      username: '',
      description: '',
      duration: 0,
      date: new Date(),
      users: []
    }
  }

  componentDidMount() {
    axios.get('http://localhost:5000/exercises/'+this.props.match.params.id)
      .then(response => {
        this.setState({
          username: response.data.username,
          description: response.data.description,
          duration: response.data.duration,
          date: new Date(response.data.date)
        })   
      })
      .catch(function (error) {
        console.log(error);
      })

    axios.get('http://localhost:5000/users/')
      .then(response => {
        if (response.data.length > 0) {
          this.setState({
            users: response.data.map(user => user.username),
          })
        }
      })
      .catch((error) => {
        console.log(error);
      })

  }

  onChangeUsername(e) {
    this.setState({
      username: e.target.value
    })
  }

  onChangeDescription(e) {
    this.setState({
      description: e.target.value
    })
  }

  onChangeDuration(e) {
    this.setState({
      duration: e.target.value
    })
  }

  onChangeDate(date) {
    this.setState({
      date: date
    })
  }

  onSubmit(e) {
    e.preventDefault();

    const exercise = {
      username: this.state.username,
      description: this.state.description,
      duration: this.state.duration,
      date: this.state.date
    }

    console.log(exercise);

    axios.post('http://localhost:5000/exercises/update/' + this.props.match.params.id, exercise)
      .then(res => console.log(res.data));

    window.location = '/';
  }

  render() {
    return (
    <div>
      <h3>Edit Exercise Log</h3>
      <form onSubmit={this.onSubmit}>
        <div className="form-group"> 
          <label>Username: </label>
          <select ref="userInput"
              required
              className="form-control"
              value={this.state.username}
              onChange={this.onChangeUsername}>
              {
                this.state.users.map(function(user) {
                  return <option 
                    key={user}
                    value={user}>{user}
                    </option>;
                })
              }
          </select>
        </div>
        <div className="form-group"> 
          <label>Description: </label>
          <input  type="text"
              required
              className="form-control"
              value={this.state.description}
              onChange={this.onChangeDescription}
              />
        </div>
        <div className="form-group">
          <label>Duration (in minutes): </label>
          <input 
              type="text" 
              className="form-control"
              value={this.state.duration}
              onChange={this.onChangeDuration}
              />
        </div>
        <div className="form-group">
          <label>Date: </label>
          <div>
            <DatePicker
              selected={this.state.date}
              onChange={this.onChangeDate}
            />
          </div>
        </div>

        <div className="form-group">
          <input type="submit" value="Edit Exercise Log" className="btn btn-primary" />
        </div>
      </form>
    </div>
    )
  }
}

Answer 1

shawnyates，清除了一些内容，这也是我想到的，但是，当在线查看文档时，axios.post也用于更新数据。

通过更改，系统现在可以成功运行。

axios.put('http://localhost:5000/exercises/update/' + this.props.match.params.id, exercise)
      .then(res => console.log(res.data));

PUT请求在使用Axios请求的前端React上不起作用

1 个答案: