When building web applications using React, we often need to restrict access to certain routes and only allow access to authenticated users. This article will explain how to create a protected route using React, react-router-dom and the Outlet component, and demonstrate how to verify whether the user is an administrator based on the value stored in localStorage.

What is protected routing?

Protected routes refer to pages that can only be accessed by users who meet specific conditions (such as being authenticated or having specific permissions, such as administrator permissions). If these conditions are not met, the user will be redirected to another page, such as a login page.

Prerequisites

Before you begin, please make sure:

• React has been configured in the project.
• React-router-dom installed:

npm install react-router-dom

Example: Protected routing with admin verification

This example will verify that the user is authenticated as an administrator by checking the value in localStorage. If not an administrator, redirect them to the login page.

• Routing configuration

First, configure the application’s main route.

import React from "react";
import { BrowserRouter as Router, Routes, Route } from "react-router-dom";
import Login from "./Login";
import Dashboard from "./Dashboard";
import ProtectedRoute from "./ProtectedRoute";

function App() {
  return (
    <Router>
      <Routes>
        <Route path="/" element={<Login />} />
        <Route element={<ProtectedRoute />} path="/dashboard/*">
          <Route index element={<Dashboard />} /> {/*  添加index路由處理/dashboard */}
        </Route>
      </Routes>
    </Router>
  );
}

export default App;

• Create ProtectedRoute component

This component verifies that the user is authenticated as an administrator before rendering the protected route. If not, redirect it to the login page.

import React from "react";
import { Navigate, Outlet } from "react-router-dom";

const ProtectedRoute = () => {
  // 從localStorage中檢查用戶是否為管理員
  const isAdmin = localStorage.getItem("role") === "admin";

  return isAdmin ? <Outlet /> : <Navigate to="/" />;
};

export default ProtectedRoute;

Code explanation:

localStorage.getItem("role"): Get the user role stored in localStorage. If the role is "admin", the Outlet component is rendered, which represents the content of the protected route. If not, use the Navigate component to redirect the user to the root path (/).

• Create a login page (Login) This page simulates the basic login process and stores the user role in localStorage.

import React from "react";
import { useNavigate } from "react-router-dom";

function Login() {
  const navigate = useNavigate();

  const handleLogin = () => {
    // 模擬登錄并保存用戶角色
    localStorage.setItem("role", "admin");
    navigate("/dashboard");
  };

  return (
    <div>
      {/* 登錄表單 */}
      <button onClick={handleLogin}>登錄</button>
    </div>
  );
}

export default Login;

• Create Dashboard page

Dashboard page is a protected route and can only be accessed by users with administrator role.

import React from "react";

function Dashboard() {
  return (
    <div>
      <h1>儀表盤</h1>
      <p>這是受保護(hù)的頁(yè)面內(nèi)容。</p>
    </div>
  );
}

export default Dashboard;

Example process

User access application:

If you are not logged in, you will see the login page (/). After logging in as an administrator, the role will be stored in localStorage and redirected to Dashboard (/dashboard). In the Dashboard, protected content (statistics and configuration) is displayed.

If a user attempts to access the Dashboard directly without admin rights, they will automatically be redirected to the login page.

Summary

Protected routing is critical for applications that handle users and permissions. Using the React Router DOM, Outlet component, and browser storage (such as localStorage), we can implement a basic access restriction system. This approach is great for small applications or learning projects, but in larger projects, a stronger authentication solution is recommended.

If you have any questions, please leave a message in the comment area! ?

The above is the detailed content of How to Create Protected Routes with React and React Router DOM. For more information, please follow other related articles on the PHP Chinese website!