Is it mandatory to run create-react-app command to create app every time?
I don't want to fire create-react-app command which provides some react module files that help to run react application.
So can you guys help me to understand, is it mandatory to every time run this command.
import React from 'react';
const App = {
return (
<div id="root">
<p>Hello this is first react application</p>
</div>
);
}
ReactDOM.render(<App />, document.getElementById('root'));
export default App;
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.8.6/umd/react-dom.production.min.js"></script>
create-react-app (cra) is used to bootstrap a new react app fast.
You can use react without using it, you can run react with only react+react-dom CDN as you already wrote in your code example.
Or you can also bootstrap it yourself if you know a little webpack, you just need the react-jsx babel preset to convert JSX syntax to React.createElement calls.
You can run it once and make a local copy to just copy over every time.
You also can build an app from scratch although that will take longer.
The majority of the 5+ minutes is downloading required dependencies for the app.
NOTE: This is not good practice as it results in never getting newer updated dependencies in your app, and you literally just keep using the old one.
If you are just making a bunch of apps to test, then that’s fine. If you are instead making a bunch of apps for production purposes, remember that part of maintenance is updating dependencies regularly as security updates are released.
Related
I am developing teams application using react js. Package.Json file showing version as 16.14.0.
But when I am getting the react version from terminal window its showing 17.0.2. Is that shows my application has 2 versions of react?
Here below is the screenshot of package.json file
As per my understanding, you have installed React JS globally as well on your OS. This way you have two versions of React JS, One for your project and another one for your global environment.
Although there is a way to know the runtime version of React in the browser.
const REACT_VERSION = React.version;
ReactDOM.render(
<div>React version: {REACT_VERSION}</div>,
document.getElementById('root')
);
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="root"></div>
In case, if you want to check React imported as a module, then go with the following code snippet.
import React from 'react';
console.log(React.version);
I'm using react with their CDN scripts (as well as react-dom and babel-standalone) that I've saved out to some files due to security practices with network connectivity, and am trying to figure out code organization.
Disclaimer: I'm aware that I need webpack or something to compile to get access to require or normal imports. I'm wondering if there's a way to organize my components without having to add a script tag in my main html for every single file.
The error that I'm getting is Uncaught ReferenceError: require is not defined. The research that I've done is saying that I need to add each file used by my other javascript with a tag in the html. This is cumbersome especially if I have a large(ish) project. It's not scalable. How can I organize the various components that I have without having to have a massive head section with all of the wonderful script tags?
I've seen some hacks, but they're older and with the advent of new react versions and browser capabilities, so I thought I'd try and see what is being used out there to solve this problem now.
p.s. this is the first experience I have with React CDN, but I've written apps in RN before.
My code is:
<html>
<head>
<script src="react.js" />
<script src="react-dom.js" />
<script src="babel.js" />
<script type="text/jsx" src="app.js" />
</head>
<body>
<div id="root" />
</body>
</html>
app.js
import Greeting from './greeting';
const App = () => {
return (
<Greeting text='Hello World' />
);
}
ReactDOM.render(
<App />,
document.getElementById('root')
);
greeting.js
const Greeting = ({ text }) => {
return (
<h1>{text}</h1>
);
}
export default Greeting;
You cannot use React or JSX in the browser without some sort of build step. React only distributes CJS, no ESM, so it needs build tooling. Babel is used to transpile, though I'm not entirely sure it makes sense to use in this context. It's a lot of overhead.
Take a look at https://blog.jim-nielsen.com/2020/react-without-build-tools/ if you want to go the no-build tools route.
You'll have to use alternative versions of React as well as alternative syntax to JSX.
Try this
NOTE: Only when you proper setup of webpack and babel. require is required of cjs modules.
if you have done your setup try following.
1. const module = require('modulename') only when module is exports as modules.export = modulename
2. Try adding this plugin babel-plugin-import in your babel config
Importing greatings.js in app.js won't work. Instead, you import all the javascript files that you are using in the HTML file only then it would work.
<script type="text/babel" src="greatings.js"></script>
in the HTML file.
No event can be added in past date .i dont want to add event on past dates,is there is any function or logic or method in react big calender
Yes, you can.
Include the necessary file for React would be fine
react.production.min.js
react-dom.production.min.js
That's the very method been used in code snippet as below:
You can try the demo in-text:
const App = () => {
const [val, setVal] = React.useState('some text');
const handleOnchange = e => {
console.log(e.target.value)
setVal(e.target.value)
}
return (
<div className="App">
<input type='text' value={val} onChange={handleOnchange} />
</div>
);
}
ReactDOM.render(<App />, document.getElementById("root"));
<div id="root"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.12.0/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.12.0/umd/react-dom.production.min.js"></script>
You need npm start to run the application because the start command runs the webpack-dev-server.
This server handles live reloading and code transpilation, as well as many other tasks for you.
If you want more customization you can npm run eject to eject your app, but it isn't recommended. Here are some alternatives to ejecting your app.
Otherwise, if it's hosting that you're worried about, you can have the npm start command run on deploy! I recommend Netlify for some free quality hosting
Since you are using react-script (which is part of the setup of create-react-app) you have everything for correct deployment at hand already. None of the mentioned manual steps are needed.
Instead, once you are ready to deploy (a version of) your app, run npm run build. This command will generated an optimized production build, bundling all your components and 3rd party libs into js files, together with the React and Webpack runtimes and put all that, including static content like images, into your build folder (location configurable). You can then copy that content to a machine with a webserver and start serving it from there, like any other web content.
I am trying to figure out how to add external JS to a React app without adding it to the HTML file in a script tag. The reason for this is that I have one component that needs access to an external script, but I can only access it as a global variable by adding /*global <variabe name>*/ at the top of the component that needs it (as far as I know), which is not ideal.
I'm basically looking for an equivalent to
const someScript = <script type="text/javascript" src="some url"></script>
but in a way that actually works 😀
This script is not needed when the app initially loads and could come in async.
You have to install react script
Use npm install react-script-tag
And Add import which is
‘import ScriptTag from 'react-script-tag';’
And then you can use it
I'm working on an old project still running jquery for frontend, java spring for the backend, and maven for building. I've been asked by my boss to introduce react into the stack so we can toy around with converting some of the pages.
My goal is to not impact the existing implementation to heavily and instead output the result of webpack into a defined directory. This way I can just point the backend at that location for pathing.
So far I have an apps folder in my workspace that contains all my react stuff that works on its own. This was generated using 'npx create-react-app folderName'.
I've somewhat read up on how to set the export but am generally confused. As a lot of resources I've found assume a new setup or a replacement of an existing setup. While I'm looking to only replace a single page currently.
I don't think create-react-app is the right tool here, since you don't create a complete application with React but incrementally add React code. I would suggest using Webpack on its own. This makes your application cleaner and easier to maintain with your other code.
If you want to keep your React code separate from your existing code you can create a library based on webpack's Authoring Libraries Guide. You can than render your components with ReactDOM.render() (Docs). Note that you can call this function (almost) unlimited times on one page which allows you to partially replace your existing code.
Replacing a page then means to create a root DOM element and call the render function:
<!-- page.html -->
<html>
<head></head>
<body>
<!-- more html -->
<div id="page-root" />
<!-- more html -->
</body>
</html>
import React from 'react'
import ReactDOM from 'react-dom'
import Page from './routes/YourPageComponent'
ReactDOM.render(<Page />, document.getElementById('page-root'));
The previous code means that you render your code in the new code which is transpiled by your webpack loaders (e.g. Babel-Loader, Typescript-Loader). If you want to render the code in the existing code, look at the Doc's about Webpack Libraries to export render functions into a global context. The following scripts are an example out of my head.
// components/PageExampleComponent.jsx
import React from 'react';
export default function({pageTitle="example"}){
return <div>
<h1>{pageTitle}</h1>
</div>
}
// libary/index.js
import PageExampleComponent from './components/PageExampleComponent';
export const MyLibrary = {
PageExampleComponent
}
The previous code requires the following (partial) Webpack config to export MyLibrary:
module.exports = {
//...
output: {
library: 'MyLibrary',
// based on a fast look into the docs, I think the following are optional:
libraryTarget: 'window',
libraryExport: 'default'
}
};
To render a component of this library, you need React and ReactDOM as scripts in your website - and of course your own library script. You can than call ReactDOM.render() in plain JavaScript:
ReactDOM.render(
React.createElement(window.MyLibrary.PageExampleComponent),
document.getElementById('page-root')
Another idea would be to move everything into Webpack. This might be easier, as you don't have barriers of different Javascript-Versions and dialects (e.g. with and without JSX support). You can even separate your jQuery code and your React code by using two entry points:
module.exports = {
//...
entry: {
oldCode: './src/jqueryIndex.js',
replacement: './src/reactIndex.js'
},
output: {
filename: "[name].js"
}
};