The easiest way to start hacking on React is using the following JSFiddle Hello World examples:
Download the starter kit to get started.
In the root directory of the starter kit, create a helloworld.html
with the following contents.
<!DOCTYPE html>
<html>
<head>
<script src="build/react.js"></script>
<script src="build/JSXTransformer.js"></script>
</head>
<body>
<div id="example"></div>
<script type="text/jsx">
/** @jsx React.DOM */
React.renderComponent(
<h1>Hello, world!</h1>,
document.getElementById('example')
);
</script>
</body>
</html>
The XML syntax inside of JavaScript is called JSX; check out the JSX syntax to learn more about it. In order to translate it to vanilla JavaScript we use <script type="text/jsx">
and include JSXTransformer.js
to actually perform the transformation in the browser.
Your React JSX code can live in a separate file. Create the following src/helloworld.js
.
/** @jsx React.DOM */
React.renderComponent(
<h1>Hello, world!</h1>,
document.getElementById('example')
);
Note:
/** @jsx React.DOM */
is required. The comment parser is very strict right now; in order for it to pick up the@jsx
modifier, two conditions are required. The@jsx
comment block must be the first comment on the file. The comment must start with/**
(/*
and//
will not work). If the parser can't find the@jsx
comment, it will output the file without transforming it.
Then reference it from helloworld.html
:
<script type="text/jsx" src="src/helloworld.js"></script>
First install the command-line tools (requires npm):
npm install -g react-tools
Then, translate your src/helloworld.js
file to plain JavaScript:
jsx --watch src/ build/
The file build/helloworld.js
is autogenerated whenever you make a change.
/** @jsx React.DOM */
React.renderComponent(
React.DOM.h1(null, 'Hello, world!'),
document.getElementById('example')
);
Update your HTML file as below:
<!DOCTYPE html>
<html>
<head>
<title>Hello React!</title>
<script src="build/react.js"></script>
<!-- No need for JSXTransformer! -->
</head>
<body>
<div id="example"></div>
<script src="build/helloworld.js"></script>
</body>
</html>
If you want to use React with browserify, webpack, or another CommonJS-compatible module system, just use the react
npm package. In addition, the jsx
build tool can be integrated into most packaging systems (not just CommonJS) quite easily.
Check out the tutorial and the other examples in the starter kit's examples
directory to learn more. Good luck, and welcome!