类型错误：无法读取未定义 React 的属性“任何”

Question

I'm new to React and I'm trying to make small app by following a Udemy tutorial. The application contains a form. When I import redux-form library into my project, I got the below console error.

package.json

"dependencies": {
    "axios": "^0.18.0",
    "babel-preset-stage-1": "^6.1.18",
    "lodash": "^3.10.1",
    "react": "16.3.2",
    "react-countdown-now": "^1.3.0",
    "react-dom": "16.3.2",
    "react-redux": "5.0.7",
    "react-router": "^3.2.0",
    "redux": "4.0.0",
    "redux-form": "^4.1.3",
    "redux-promise": "^0.5.3"
  }

post_new.js contains the form.

import React, { Component } from 'react';
import { reduxForm } from 'redux-form';

class PostsNew extends Component {
    render() {
        return (
            <form onSubmit={handleSubmit}>
                <h3>Create a new post</h3>
                <div className="form-group">
                    <label>Title</label>
                    <input type="text" className="form-control" />
                </div>
                <div className="form-group">
                    <label>Categories</label>
                    <input type="text" className="form-control"/>
                </div> 
                <div className="form-group">
                    <label>Content</label>
                    <textarea className="form-control"/>
                </div>

                <button type="submit" className="btn btn-primary">Submit</button>
            </form>    
        );
    }
}
export default reduxForm(
    {
        form: 'PostsNewForm',
        fields: ['title','categories','content']
    }
)(PostsNew);

also imported redux-form in reducers _> index.js

import { combineReducers } from 'redux';
import PostReducer from './reducer_posts';
import { reducer as formReducer } from 'redux-form';

const rootReducer = combineReducers({
  posts: PostReducer,
  form: formReducer
});

export default rootReducer;

Answer 1

Use version 5.3.6. It will definitely solve the problem.

Answer 2

I ones had same error. How I resolved it was to upgrade the redux-form to v5.2.6. Then stop the server in your terminal using Ctrl +c, run npm i to bring in redux -form dependences. then restart your project.

This should fix the error. I hope this helps.

Answer 3

Installing updates using package-manager is not enough. You need to reinstall your localhost after updating redux-form. using:

• Ctrl + 'C'
• npm i
• npm start