javascript - Programmatically Navigate using react-router

Question

I am developing an application in which I check if the user is not loggedIn. I have to display the login form, else dispatch an action that would change the route and load other component. Here is my code:

render() {
    if (isLoggedIn) {
        // dispatch an action to change the route
    }
    // return login component
    <Login />
}

How can I achieve this as I cannot change states inside the render function.

Answer 1

Considering you are using react-router v4

Use your component with withRouter and use history.push from props to change the route. You need to make use of withRouter only when your component is not receiving the Router props, this may happen in cases when your component is a nested child of a component rendered by the Router and you haven't passed the Router props to it or when the component is not linked to the Router at all and is rendered as a separate component from the Routes.

import {withRouter} from 'react-router';

class App extends React.Component {
     ...
     componenDidMount() {
        // get isLoggedIn from localStorage or API call
        if (isLoggedIn) {
             // dispatch an action to change the route
             this.props.history.push('/home');
        }
     }
     render() {
         // return login component
         return <Login />
    }
}


export default withRouter(App);

Important Note

If you are using withRouter to prevent updates from being blocked by shouldComponentUpdate, it is important that withRouter wraps the component that implements shouldComponentUpdate. For example, when using Redux:

// This gets around shouldComponentUpdate

withRouter(connect(...)(MyComponent))

// This does not

connect(...)(withRouter(MyComponent))

or you could use Redirect

import {withRouter} from 'react-router';

class App extends React.Component {
     ...
     render() {
         if(isLoggedIn) {
              return <Redirect to="/home"/>
         }
         // return login component
         return <Login />
    }
}

With react-router v2 or react-router v3, you can make use of context to dynamically change the route like

class App extends React.Component {
     ...
     render() {
         if (isLoggedIn) {
             // dispatch an action to change the route
             this.context.router.push('/home');
         }
         // return login component
         return <Login />
    }
}

App.contextTypes = {
    router: React.PropTypes.object.isRequired
}
export default App;

or use

import { browserHistory } from 'react-router';
browserHistory.push('/some/path');