Develop Reference

React and Node show nothing when i run the localhost

i have a issue with my projec, i am doing everything just like the man of tutorial, but when i run the server, my http://localhost:3000/ show me nothing, there is not error, but neither do nothing.
All this hapenned when i imported the react-roter-dom and changed the App.js
from This
function App() {
return (
<div>
<h1>Hello world</h1>
</div>
);
}
export default App;
to this
import React from "react";
import { createRoot } from "react-dom/client";
import {
createBrowserRouter,
RouterProvider,
Route,
Link,
} from "react-router-dom";
import Login from "./pages/Login";
import Register from "./pages/Register"
const router = createBrowserRouter([
{
path: "/",
element: <div> This is home world!</div>,
},
]);
function App() {
return (
<div>
<RouterProvider router={router}> </RouterProvider>
</div>
);
}
export default App;
and it should at least show the message "this is home world"
Please help me, Because i dont know what is hapening, no show error but it doesn't do anything either
this is what i got
after the router dom
before put the router dom show me " hello world" with this
function App() {
return (
<div>
<h1>Hello world</h1>
</div>
);
}
export default App;
index.JS
import React from 'react';
import ReactDOM from 'react-dom/client';
import App from './App';
const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(
<React.StrictMode>
<App />
</React.StrictMode>
);
dev console
App.js
import React from "react";
import { createRoot } from "react-dom/client";
import {
createBrowserRouter,
RouterProvider,
Route,
Link,
} from "react-router-dom";
import Login from "./pages/Login";
import Register from "./pages/Register"
const router = createBrowserRouter([
{
path: "/",
element: <div> This is home world!</div>,
},
]);
function App() {
return (
<div>
<RouterProvider router={router}/>
</div>
);
}
export default App;
the consolo show me these errors

I think you just didn't save the initial code. You might want to turn on autosave on your vs code. And use the normal react render method for your index and app files.
Index.js :
import React from 'react';
import ReactDOM from 'react-dom';
import App from './App';
ReactDOM.render(
<App/>,
document.getElementById('root'));
App.js:
import React from 'react'
const App = () => {
return (
<div>
<h1>GPT-3</h1>
</div>
)
}
export default App
Try to run this but save the code or turn on auto-save

React shows blank white screen for localhost:3000

Building a test web3 website and can't figure out why to react is showing blank. Hoping you guys can help!
App.js
import { useState } from 'react';
import './App.css';
import MainMint from "./MainMint";
import NavBar from "./NavBar";
function App() {
const [accounts, setAccounts] = useState([]);
return (
<div className="App">
<NavBar accounts={accounts} setAccounts={setAccounts} />
<MainMint accounts={accounts} setAccounts={setAccounts} />
</div>
);
}
export default App;
Index.js
import React from 'react';
import ReactDOM from 'react-dom/client';
import './index.css';
import App from './App';
const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(
<React.StrictMode>
<App />
</React.StrictMode>
);

My App Component will not render with React

I am doing React project with typescript form scratch, and for some reason, I can't get the App component to render. I know the file path is correct. The Error says: Module not found: Error: Can't resolve './App' in '/Users/michaelhorvilleur/Desktop/Codecademy/react-porfolio/src'
import React from "react";
import ReactDOM from "react-dom";
import App from "./App";
ReactDOM.render(<App />, document.getElementById("#root"));
import React, { useState } from "react";
const App = () => {
return (
<div>
<h1>App</h1>
</div>
);
};
export default App;

import { StrictMode } from "react";
import { createRoot } from "react-dom/client";
import App from "./App.tsx";
const rootElement = document.getElementById("root");
const root = createRoot(rootElement);
root.render(
<StrictMode>
<App />
</StrictMode>
);

Make sure the App.js file is positioned in src folder

Why do my props not work in grandchild component?

Tried to transfer data from 2 components to one using the same method, but it is working only for 50%. There are 3 documents: App.js, Hort.js, Hord.js. Transfering from app.js to hort.js is working, but from hord.js to hort.js isn't. What could be the reason?
App.js:
import React from 'react'
import Hort from './Hort'
function App(props) {
const text1 = 'check1'
return (
<Hort test1={text1} />
);
}
export default App;
Hord.js:
import React from 'react'
import Hort from './Hort'
function Hord(props) {
const text2 = 'check2'
return (
<Hort test2={text2} />
);
}
export default Hord;
Hort.js:
import React from 'react'
import App from './App'
import Hord from './Hord'
function Hort(props) {
return (
<div>
<h1>Just {props.test1}</h1>
<h2>Just {props.test2}</h2>
</div>
)
}
export default Hort;

You are never rendering <Hord>, if a component is never rendered, it won't render what's inside it.
In your index.js, you probably have code that looks like this:
import { StrictMode } from "react";
import ReactDOM from "react-dom";
import App from "./App";
const rootElement = document.getElementById("root");
ReactDOM.render(
<StrictMode>
<App />
</StrictMode>,
rootElement
);
This code indicates that the <App> component will get rendered in the root element from your index.html.
So starting from the <App> component, you can build your component tree, because you never call <Hord>, it will never render, nor will the components rendered inside <Hord>.
Render <Hord> inside your <App> component.
import React from 'react'
import Hort from './Hort'
import Hord from './Hord'
function App(props) {
const text1 = 'check1'
return (
<Hort test1={text1} />
<Hord />
);
}
export default App;
As mentioned in the comments, you shouldn't import components that could cause infinite loops.
import React from 'react'
// * removed imports
function Hort(props) {
return (
<div>
<h1>Just {props.test1}</h1>
<h2>Just {props.test2}</h2>
</div>
)
}
export default Hort;

You should not use <Route> or withRouter() outside a <Router>

I have wrapped my index.js file to support a Redux Store and React-Router-v4.
However, when I try to run a basic test, I get the following error message:
Invariant Violation: You should not use <Route> or withRouter() outside a <Router>
Here is what my index.js looks like:
import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import { BrowserRouter } from 'react-router-dom';
import registerServiceWorker from './registerServiceWorker';
// Redux
import { Provider } from 'react-redux';
import store from "./store/index";
ReactDOM.render((
<Provider store={store}>
<BrowserRouter>
<App />
</BrowserRouter>
</Provider>
), document.getElementById('root'));
registerServiceWorker();
and here is my App.js:
import React, { Component } from 'react';
import { ScaleLoader } from 'react-spinners';
import { withRouter } from 'react-router';
import Header from './components/Header';
import Footer from './components/Footer';
import Main from './Main';
import './styles/styles.scss';
// Redux
import { connect } from 'react-redux';
import store from "./store/index";
import { isLoading } from "./actions/index";
class App extends Component {
constructor() {
super();
store.dispatch(isLoading(true));
}
componentDidUpdate(prevProps) {
if (this.props.location.pathname !== prevProps.location.pathname) {
store.dispatch(isLoading(true));
}
}
render() {
return (
<div className='App'>
<Header />
<div className='App__wrapper'>
<div className={'loading-spinner ' + (this.props.isLoading ? null : '--hide-loader')}>
<ScaleLoader
color={'#123abc'}
loading={this.props.isLoading}
/>
</div>
<Main />
</div>
<Footer />
</div>
);
}
}
const mapStateToProps = (state) => ({ isLoading: state.isLoading });
export default withRouter(connect(mapStateToProps)(App));
Since I'm using withRouter to wrap for navigation, is this method discouraged? Should I be setting up withRouter at the index.js level?
Thank you!

Try importing your BrowserRouter like this:
import { BrowserRouter as Router } from 'react-router-dom'
Then replace everywhere it appears BrowserRouter with Router instead.