Сделали отложеную загрузку и перехват исключений

package-lock.json

@@ -9,7 +9,9 @@
       "version": "0.0.0",
       "dependencies": {
         "react": "^19.1.0",
-        "react-dom": "^19.1.0"
+        "react-dom": "^19.1.0",
+        "react-error-boundary": "^6.1.2",
+        "react-router-dom": "^7.17.0"
       },
       "devDependencies": {
         "@eslint/js": "^9.25.0",
@@ -1600,6 +1602,19 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/cookie": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/cookie/-/cookie-1.1.1.tgz",
+      "integrity": "sha512-ei8Aos7ja0weRpFzJnEA9UHJ/7XQmqglbRwnf2ATjcB9Wq874VKH9kfjjirM6UhU2/E5fFYadylyhFldcqSidQ==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=18"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/express"
+      }
+    },
     "node_modules/cross-spawn": {
       "version": "7.0.6",
       "resolved": "https://registry.npmjs.org/cross-spawn/-/cross-spawn-7.0.6.tgz",
@@ -2461,6 +2476,15 @@
         "react": "^19.1.0"
       }
     },
+    "node_modules/react-error-boundary": {
+      "version": "6.1.2",
+      "resolved": "https://registry.npmjs.org/react-error-boundary/-/react-error-boundary-6.1.2.tgz",
+      "integrity": "sha512-3DpCr5HVdZ0caUjYE/kIHBEJN0mNP3ZCgf16c48uJ5TbWjorKVp+YG8W3XqlJ7vJAVNw6wNIImyPXmFydwmyng==",
+      "license": "MIT",
+      "peerDependencies": {
+        "react": "^18.0.0 || ^19.0.0"
+      }
+    },
     "node_modules/react-refresh": {
       "version": "0.17.0",
       "resolved": "https://registry.npmjs.org/react-refresh/-/react-refresh-0.17.0.tgz",
@@ -2471,6 +2495,44 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/react-router": {
+      "version": "7.17.0",
+      "resolved": "https://registry.npmjs.org/react-router/-/react-router-7.17.0.tgz",
+      "integrity": "sha512-FDELK7rTMlCHO5+reyXsPlmfr7N1F91lPHsWYfMEGQm/KQ+F4JFM8jGoeQDmDvdTs93Fw9aSilH+uKRb4/jXvQ==",
+      "license": "MIT",
+      "dependencies": {
+        "cookie": "^1.0.1",
+        "set-cookie-parser": "^2.6.0"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      },
+      "peerDependencies": {
+        "react": ">=18",
+        "react-dom": ">=18"
+      },
+      "peerDependenciesMeta": {
+        "react-dom": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/react-router-dom": {
+      "version": "7.17.0",
+      "resolved": "https://registry.npmjs.org/react-router-dom/-/react-router-dom-7.17.0.tgz",
+      "integrity": "sha512-fyU2yjGups/hE6Xz0I5ZYbVL8Gx29eCjgpHaRaTaVU+OOAdfRX05KsvyRm0GO8YQwOkhpU3MurW1jyMUJn+zSw==",
+      "license": "MIT",
+      "dependencies": {
+        "react-router": "7.17.0"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      },
+      "peerDependencies": {
+        "react": ">=18",
+        "react-dom": ">=18"
+      }
+    },
     "node_modules/resolve-from": {
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/resolve-from/-/resolve-from-4.0.0.tgz",
@@ -2544,6 +2606,12 @@
         "semver": "bin/semver.js"
       }
     },
+    "node_modules/set-cookie-parser": {
+      "version": "2.7.2",
+      "resolved": "https://registry.npmjs.org/set-cookie-parser/-/set-cookie-parser-2.7.2.tgz",
+      "integrity": "sha512-oeM1lpU/UvhTxw+g3cIfxXHyJRc/uidd3yK1P242gzHds0udQBYzs3y8j4gCCW+ZJ7ad0yctld8RYO+bdurlvw==",
+      "license": "MIT"
+    },
     "node_modules/shebang-command": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/shebang-command/-/shebang-command-2.0.0.tgz",

package.json

@@ -11,7 +11,9 @@
   },
   "dependencies": {
     "react": "^19.1.0",
-    "react-dom": "^19.1.0"
+    "react-dom": "^19.1.0",
+    "react-error-boundary": "^6.1.2",
+    "react-router-dom": "^7.17.0"
   },
   "devDependencies": {
     "@eslint/js": "^9.25.0",

src/App.jsx

@@ -1,108 +1,25 @@
-import React from 'react'
+import { Suspense, lazy } from 'react'
+import { ErrorBoundary } from 'react-error-boundary'
 
-class MyComponent extends React.Component {
+const LazyComponent = lazy(() => import('./MyComponent'))
-    constructor(props) {
-        super(props);
-        this.state = { data: null };
-        this.handleClick = this.handleClick.bind(this);
-    }
 
-    render() {
+function ErrorFallBack({error, resetErrorBoundary }) {
-        return (
+    return (
-            <div>
+        <div>
-            {this.state.data ? (
+            <h2>Что то сломалось</h2>
-                    <div>Данные: {this.state.data}</div>
+            <button onClick={resetErrorBoundary}></button>
-                ) : (
+        </div>
-                    <div>Загрузка...</div>
+    )
-                )}
-                <button onClick={this.handleClick}>Обновить</button>
-            </div>
-        )
-    }
-    
-    componentDidMount() {
-        fetch('https://api.example.com/data')
-        .then(responce => responce.json())
-        .then(json => this.setState({data: json}));
-        
-        this.timerId = setInterval(()=> console.log('Tick'), 1000);
-    }
-    
-    componentWillUnmout() {
-        clearInterval(this.timerId);
-    }
-    
-    handleClick() {
-        this.setState({data: 'Данные'})
-    }
-}
-
-class MyComponent2 extends React.Component {
-    controller = new AbortController()
-
-    componentDidMount() {
-        fetch('https://api.example.com/data',{ singnal: this.controller.signal })
-        .then(responce => responce.json())
-        .then(json => this.setState({data: json}))
-        .catch(error => {
-            if(error.name == 'AbortError') {
-                console.log('Aborted');
-            } else {
-                console.log('Other error',error);
-            }
-        });
-    }
-
-    componentWillUnmount() {
-        this.controller.abort()
-    }
-}
-class MyComponent3 extends React.Component {
-    componentDidMount() {
-        this.loadData();
-    }
-    
-    async loadData() {
-        try {
-            const response = await fetch('https://api.example.com/data');
-            const data = await response.json();
-            this.setSate({ data });
-        } catch {
-            console.log('error');
-        }
-    }
-}
-
-class Timer extends React.Component {
-    constructor(props) {
-        super(props);
-        this.state = { seconds: 0 }
-    }
-    
-    componentDidMount() {
-        console.log('Timer mounted');
-        this.interval = setInterval(()=>{
-            this.setState(prevState => ({seconds: prevState.seconds + 1}))
-        },1000);
-    }
-    
-    componentWillUnmount() {
-        console.log('Timer unmount');
-        clearInterval(this.interval);
-    }
-    render() {
-        return <h2>Прошло секунд: {this.state.seconds}</h2>
-    }
 }
 
 function App() {
-    const [show,setShow] = React.useState(true);
-    
 	return (
 		<>
-			<h1>Таймер с классом</h1>
+			<ErrorBoundary FallBackComponent={ErrorFallBack}>
-            <button onClick={()=>setShow(prev => !prev)}>{show ? 'Скрыть' : 'Показать'} таймер</button>
+                <Suspense fallback={<div>Загрузка ...</div>}>
-            {show && <Timer />}
+			        <LazyComponent />
+                </Suspense>
+            </ErrorBoundary>
 		</>
 	)
 }

src/main.jsx

@@ -4,5 +4,7 @@ import { createRoot } from 'react-dom/client'
 import App from './App.jsx'
 
 createRoot(document.getElementById('root')).render(
+	<StrictMode>
 		<App />
+	</StrictMode>
 )