React router v4 - How do you access the state that

Question

I am making a login page with the help of react that redirects to another page when the login is successful. Let me call the component that gets rendered when the login is successful 'A'. I want to pass data fetched from the database to component A and I am doing so by passing it in the 'state' attribute of the 'Redirect' component. However, I do not understand how to access this state in the 'Route' component that ultimately renders component A. Can anyone tell me how?

My code is as follows:

Login.js:

import React from 'react'
import Center from 'react-center'
import PropTypes from 'prop-types'
import classnames from 'classnames'
import isEmpty from 'lodash/isEmpty'
import { browserHistory } from 'react-router'
import { Route, Redirect } from 'react-router-dom'

import Courses from '../pages/Courses'
import Logo from './shared/Logo'
import Routes from './Routes'
import Tiles from './Tiles'

export default class LoginForm extends React.Component
{
    constructor()
    {
        super()

        this.state = 
        {
            username: '',
            password: '',
            student: false,
            instructor: false,
            error_password: '',
            error_username: ''
        }

        this.onChange = this.onChange.bind(this)
        this.onSubmit = this.onSubmit.bind(this)
    }

    onChange(event)
    {
        this.setState({error_username:'', error_password:'', [event.target.name]: event.target.value})
        console.log(this.state)
        event.preventDefault()
    }

    onSubmit(event)
    {
        event.preventDefault()
        if (this.state.username && this.state.password)
        {
            this.props.loginRequest({username: this.state.username, password: this.state.password})
            .then(response => 
                {
                    this.setState(    // THE SERVER WILL SEND THE RELEVANT DATA HERE
                    {
                        username: '',
                        password: '',
                        student: response.data.student, 
                        error_username: response.data.error_username, 
                        error_password: response.data.error_password
                    })
                })
        }
        else
            this.setState({error_username: 'Please enter username', error_password: 'Please enter password.'})
    }

    render()
    {
        const styles =
        {
            buttonStyle:
            {
                margin: 'auto',
                width: '83'
            }
        }

        if (this.state.student)  ///  REDIRECT IS HAPPENING HERE
        {
            return (
            <Redirect to = {{
                pathname: '/loginS/student',
                state: { course_information }  /// HERE I WILL SEND THE RELEVANT INFORMATION THAT THE SERVER SENDS TO THE COMPONENT A 
            }}/> )
        }
        else if (this.state.instructor)
        {
            return <Redirect to = {'/loginI/instructor'} />
        }
        else 
        {
            // NOT RELEVANT
        }

        return(

            display 
        )
    }
}

LoginForm.propTypes = 
{
    loginRequest: PropTypes.func.isRequired
}

Routes.js

import React from 'react'
import { Switch, Route } from 'react-router-dom'

import Courses from '../pages/Courses'
import Login from './Login'
import Dashboard from './Dashboard'
import StudentsHandle from './StudentsHandle'
import CourseItem from './CourseItem'
import SemesterItem from './SemesterItem'
import Logo from './shared/Logo'
import Tiles from './Tiles'

export default class Routes extends React.Component
{
    render() 
    {
        return(
            <Switch>
                <Route exact path = '/' component = { Dashboard }/>
                <Route exact path = '/loginS' component = { Login } />
                <Route path = '/loginS/student' render = { (props) =>  < Tiles data = {this.props.coursesData} />} /> // HOW DO I ACCESS THE PROPS REDIRECT SENDS HERE?
                <Route path = '/instructor' component = { Courses } />
            </Switch>
        );
    }
} 

Answer 1

You can use the location prop to access the state you have passed. Visit React-Router for reference. When you want to access that state, you can do it by this.props.location.state.