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React Project development environment building command create-react-app is too convenient

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Abstract

Hello everyone It’s me candle.
In this time we will build a “react” development environment with create-react-app command and try to hello world.
Past react development was created by installing babel and other packages from npm on your own using gulp or webpack.
Past react development installed babel and other packages from npm and built servers with gulp and webpack.
If you use the create-react-app command, you can create react environment easily.
Let’s do it.


Precondition

Node is already installed


Installing the create-react-app command

You can install the create-react-app command from npm.
We will use this command in the computer as a whole, so we install it with -g flag.

npm install -g create-react-app

Create react project

We start to create react project with create-react-app.
This is the general making method.

create-react-app projet_name_here

Let’s create helloworld project in this time.
It is ok the location of the directory anywhere. I make it on the desktop for ease of explanation.

create-react-app helloworld

After installing you move to the project.

cd helloworld
ls


Launching the server

When you move to the project, start the server with npm start.

npm start

A message like this appears

It will be successful if the browser opens and the following page appears.

Writing hello world program

Let’s do it as a first practice.

  1. Create a src/components/Input.js componet
  2. Edit src/App.js

Create src/components/Input.js component

At first let’s create the Input.js component.
We do not have the components folder yet in the src folder.
We make the components folder and Input.js

mkdir src/components
touch src/components/Input.js

Open the src/components/Input.js and write it.

import React from 'react';

const Input = (props) => <input name={props.name} type={props.type} onChange={props.onChange} />

Input.propTypes = {
  onChange: React.PropTypes.func,
  name: React.PropTypes.string,
  type: React.PropTypes.string
}

Input.defaultProps ={
  name: '',
  type: 'text'
}

module.exports = Input;

Save it.

Rewrite src/App.js

The main program of react is src/App.js. Open it with your favorite editor.

emacs src/App.js

Rewrite like this code.

import React from 'react';
import Input from './components/Input'

class App extends React.Component{
  constructor(){
    super();
    this.state = {
      txt: 'hello world'
    }
  }

  update(e){
    this.setState({
      txt: e.target.value
    })
  }

  render(){
    return(
      <div>
        <p>Text: {this.state.txt}</p>
        <Input onChange={this.update.bind(this)} />
      </div>
    )
  }
}

export default App;

Save it.

Check it in the browser

Access http://localhost:3000 in the browser.
You write character in the text field, the text of “hello world” will be overwritten.


Conclusion

Until now React programmers were building the environment in various ways, but it seems that this is the one of best practice.

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I work in the venture company as a CTO. I start to write program in University, first I learned java, C++ and PHP. In the company, I'm developing web services by Rails. I do like to automation.