Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript Express Basics Deeper into Routing with Express Redirects

Shawn Rieger
Shawn Rieger
9,916 Points
Posted by Shawn Rieger
Shawn Rieger
9,916 Points

Error in Express when rendering with ES6 shorthand.

this works

app.get('/', (req, res) => {
  res.render('index', {name: req.cookies.username});
});

this does not

app.get('/', (req, res) => {
  const name = req.cookies.username;
  res.render('index', name);
});

TypeError: Cannot create property '_locals' on string 'Andrew'
    at ServerResponse.render (/Users/riegersn/Code/treehouse/flashcards/node_modules/express/lib/response.js:957:16)
    at app.get (/Users/riegersn/Code/treehouse/flashcards/app.js:12:7)
    at Layer.handle [as handle_request] (/Users/riegersn/Code/treehouse/flashcards/node_modules/express/lib/router/layer.js:95:5)
    at next (/Users/riegersn/Code/treehouse/flashcards/node_modules/express/lib/router/route.js:137:13)
    at Route.dispatch (/Users/riegersn/Code/treehouse/flashcards/node_modules/express/lib/router/route.js:112:3)
    at Layer.handle [as handle_request] (/Users/riegersn/Code/treehouse/flashcards/node_modules/express/lib/router/layer.js:95:5)
    at /Users/riegersn/Code/treehouse/flashcards/node_modules/express/lib/router/index.js:281:22
    at Function.process_params (/Users/riegersn/Code/treehouse/flashcards/node_modules/express/lib/router/index.js:335:12)
    at next (/Users/riegersn/Code/treehouse/flashcards/node_modules/express/lib/router/index.js:275:10)
    at cookieParser (/Users/riegersn/Code/treehouse/flashcards/node_modules/cookie-parser/index.js:70:5)

2 Answers

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

If you want to use the object literal shorthand you need to use the object brackets around name so it knows you are passing an object and not just the variable name.

res.render('index', {name});   // Same as res.render('index', { name: name });
Shawn Rieger
Shawn Rieger
9,916 Points
Shawn Rieger
Shawn Rieger
9,916 Points

Yes, I realized after I submitted this and went back to the video. Opps. Thank you!

edinjusupovic
edinjusupovic
5,664 Points
edinjusupovic
edinjusupovic
5,664 Points

In the top example, you're passing an object whereas in the bottom example, it's just a string.