Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

JavaScript Node.js Basics (2014) Building a Command Line Application Using try and catch

rd. ln.
rd. ln.
7,851 Points

In the catch block user call console.error to print out the error's message property. WHAT????

What is this even talking about?

app.js
var message = "This fucking sucks. He should find a new career other than teaching."
try {
var jsonString = 'This is not a JSON String';
var jsonObject = JSON.parse(jsonString);
} catch (error) {
  console.error(message);
}

3 Answers

William Li
PLUS
William Li
Courses Plus Student 26,867 Points

what it is talking about is var jsonObject = JSON.parse(jsonString); this statement can go wrong, you need to catch the exception and print its message property out with console.error.

Here's one way to do it.

var jsonString = 'This is not a JSON String';
try {
  var jsonObject = JSON.parse(jsonString);
} catch(error) {
  console.error(error.message);
};
Andrew Chalkley
STAFF
Andrew Chalkley
Treehouse Guest Teacher

The error passed in to the catch clause is an object. A variable encapsulated by an object that can be accessed by using dot notation is known as a property.

The error object has a property called message.

const jsonString = 'This is not a JSON String'; try { const jsonObject = JSON.parse(jsonString); } catch(error) { console.error(error.message); };