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JavaScript React Router 4 Basics Navigating, Nesting and Redirecting Routes Using the Match Object

Posted by Luke Miler
Luke Miler
9,165 Points

Cannot read property 'url' of undefined when using match.url?

When using Guil's code line by line (even copied and pasted from download files) I get TypeError: Cannot read property 'url' of undefined > <li><NavLink to={`${match.url}/html`}>HTML</NavLink></li>

Am I missing something? Or is there an updated solution to this?

3 Answers

James Crosslin
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James Crosslin
Full Stack JavaScript Techdegree Graduate 16,882 Points
James Crosslin
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James Crosslin
Full Stack JavaScript Techdegree Graduate 16,882 Points

I know I'm late on this one, but I'm pretty sure this is a failure to destructure match from the values object as a parameter for our Courses function like so:

Courses.js

const Courses = ({ match }) => (
  <div className="main-content courses">
 //etc, etc
}
Ryan Agatep
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Ryan Agatep
Full Stack JavaScript Techdegree Graduate 17,705 Points
Ryan Agatep
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Ryan Agatep
Full Stack JavaScript Techdegree Graduate 17,705 Points

I can't get the {match.path} or {match.url} to work with my code. I get the same error message as OP. Any thoughts? Here's my version:

import React from 'react';
import { Route, NavLink, Redirect } from 'react-router-dom';

import HTML from './courses/HTML';
import CSS from './courses/CSS';
import JavaScript from './courses/JavaScript';

const Courses = ({match}) => (
  <div className="main-content courses">
    <div className="course-header group">
      <h2>Courses</h2> 
      <ul className="course-nav">
        <li><NavLink to='html'>HTML</NavLink></li>
        <li><NavLink to='css'>CSS</NavLink></li>
        <li><NavLink to='javascript'>JavaScript</NavLink></li>
      </ul>
    </div>

    {/* Write routes here... */}
    <Route exact path="/courses" render={ () => <Redirect to="/courses/html"></Redirect> }></Route>
    <Route path="/courses/html">
      <HTML />
    </Route>
    <Route path="/courses/css">
      <CSS />
    </Route>
    <Route path="/courses/javascript">
      <JavaScript />
    </Route>
  </div>
);

export default Courses;