Nav Link Active state logic React

NavLink.js

import React from 'react';
import { Link } from 'react-router-dom';

class NavLink extends React.Component {
    render() {
        //let isActive = this.context.router.route.location.pathname === this.props.to;
        let isActive = window.location.pathname === this.props.to;
        let className = isActive ? 'active ' + this.props.className : this.props.className;

        return(
            <Link {...this.props} className={className}>
                {this.props.children}
            </Link>
        );
    }
}

export default NavLink;