startit/react_test/spa_react/src/App.js

import React, { Component } from "react";
import { Route, NavLink, HashRouter, Routes } from "react-router-dom";

import Home from "./Home";
import About from "./About";
import Contact from "./Contact";

class App extends Component {
  render() {
    return (
      <HashRouter>
      <div className="App">
        <h1>A Simple SPA made using React</h1>
        <ul className="header">
          <li><NavLink to="/">Home</NavLink></li>
          <li><NavLink to="/about">About</NavLink></li>
          <li><NavLink to="/contact">Contact</NavLink></li>
        </ul>
        <div className="content">
          <Routes>
          <Route exact path="/" element={<Home />}></Route>
          <Route path="/about" element={<About />}></Route>
          <Route path="/contact" element={<Contact />}></Route>
          </Routes>
        </div>
      </div>
      </HashRouter>
    );
  }
}

export default App;