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Exercise: JS Error Handling

Objective#

In this exercise, we will be practicing error handling in JavaScript by implementing selective catching, strict mode and try/catch/finally blocks.

Steps#

Getting Started#

Exercise Repo: JS Error Handling

  1. Open your command line and navigate to your repos directory (if you do not have a repos folder, then you can use mkdir repos to create one)
  2. Use this template repository to start a new project in your repos folder: git clone <repo_link>
  3. cd repo_name to navigate into your new repo directory
  4. Start Visual Studio Code and select 'Open Folder'. Then select repo_name to open the folder in the editor (or just type code . in your terminal inside the repo directory)
  5. Follow the instructions on the README.md file to complete exercises
  6. Open the app.js file to get started

Exercise 1: Enable Strict Mode#

Complete the following in your app.js file

  1. Enable JavaScript's "Strict Mode" for the file

Exercise 2: Function Syntax Debugging#

Complete the following in your app.js file

  1. There is a problem with the function syntax. Fix the issue before you finish.

HINT: The issue will cause data to be read as null.

Exercise 3: Using Try/Catch#

Complete the following in your app.js file

  1. Add a try/catch block in the function body
  2. Try to return the data parsed to JSON
  3. Catch any raised exceptions
  4. If an exception is caught:
    1. Print the error to the console
    2. Return null

On Complete#

When you are finished, your console should resemble the following:

null
{ success: true }