//客戶端index.jsimport React from 'react';import ReactDOM from 'react-dom';import './index.css';import App from './App';import { BrowserRouter as Router, Route, Switch } from 'react-router-dom'import registerServiceWorker from './registerServiceWorker'; ReactDOM.render(<div><Router><Route path='/supplies/:client_id' component={App}></Route></Router></div>, document.getElementById('root'));App.jsclass App extends Component {   state = {users: [],          products:[]};      steps = ['紡紗','織布','后整','檢查入庫','發貨'];   componentDidMount() {    console.log(this.props.params.client_id);  //不對這里     fetch('/supplies/320001')       .then(res => res.json())       .then(products => this.setState({ products }));   }訪問http://localhost:3000/supplies/320001http://localhost:3000/supplies/420001如何獲取320001 或 420001