# Using Typescript with React (JS & native)
# ReactJS component written in Typescript
You can use ReactJS's components easily in TypeScript. Just rename the 'jsx' file extension to 'tsx':
//helloMessage.tsx:
var HelloMessage = React.createClass({
render: function() {
return <div>Hello {this.props.name}</div>;
}
});
ReactDOM.render(<HelloMessage name="John" />, mountNode);
But in order to make full use of TypeScript's main feature (static type checking) you must do a couple things:
1) convert React.createClass to an ES6 Class:
//helloMessage.tsx:
class HelloMessage extends React.Component {
render() {
return <div>Hello {this.props.name}</div>;
}
}
ReactDOM.render(<HelloMessage name="John" />, mountNode);
For more info on converting to ES6 look here (opens new window)
2) Add Props and State interfaces:
interface Props {
name:string;
optionalParam?:number;
}
interface State {
//empty in our case
}
class HelloMessage extends React.Component<Props, State> {
render() {
return <div>Hello {this.props.name}</div>;
}
}
// TypeScript will allow you to create without the optional parameter
ReactDOM.render(<HelloMessage name="Sebastian" />, mountNode);
// But it does check if you pass in an optional parameter of the wrong type
ReactDOM.render(<HelloMessage name="Sebastian" optionalParam='foo' />, mountNode);
Now TypeScript will display an error if the programmer forgets to pass props. Or if trying to pass in props that are not defined in the interface.
# Typescript & react & webpack
Installing typescript, typings and webpack globally
npm install -g typescript typings webpack
Installing loaders and linking typescript
npm install --save-dev ts-loader source-map-loader npm link typescript
Linking TypeScript allows ts-loader to use your global installation of TypeScript instead of needing a separate local copy typescript doc (opens new window)
installing .d.ts
files with typescript 2.x
npm i @types/react --save-dev
npm i @types/react-dom --save-dev
installing .d.ts
files with typescript 1.x
typings install --global --save dt~react
typings install --global --save dt~react-dom
tsconfig.json
configuration file
{
"compilerOptions": {
"sourceMap": true,
"noImplicitAny": true,
"module": "commonjs",
"target": "es5",
"jsx": "react"
}
}
webpack.config.js
configuration file
module.exports = {
entry: "<path to entry point>",// for example ./src/helloMessage.tsx
output: {
filename: "<path to bundle file>", // for example ./dist/bundle.js
},
// Enable sourcemaps for debugging webpack's output.
devtool: "source-map",
resolve: {
// Add '.ts' and '.tsx' as resolvable extensions.
extensions: ["", ".webpack.js", ".web.js", ".ts", ".tsx", ".js"]
},
module: {
loaders: [
// All files with a '.ts' or '.tsx' extension will be handled by 'ts-loader'.
{test: /\.tsx?$/, loader: "ts-loader"}
],
preLoaders: [
// All output '.js' files will have any sourcemaps re-processed by 'source-map-loader'.
{test: /\.js$/, loader: "source-map-loader"}
]
},
// When importing a module whose path matches one of the following, just
// assume a corresponding global variable exists and use that instead.
// This is important because it allows us to avoid bundling all of our
// dependencies, which allows browsers to cache those libraries between builds.
externals: {
"react": "React",
"react-dom": "ReactDOM"
},
};
finally run webpack
or webpack -w
(for watch mode)
Note: React and ReactDOM are marked as external