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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
56,414 Points
Seth Kroger
Seth Kroger
56,414 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.