Lab 8: Trivia

Write a webpage that lets users answer trivia questions.

Getting Started

Open VS Code.

Start by clicking inside your terminal window, then execute cd by itself. You should find that its “prompt” resembles the below.

$

Click inside of that terminal window and then execute

wget https://cdn.cs50.net/2021/fall/labs/8/trivia.zip

followed by Enter in order to download a ZIP called trivia.zip in your codespace. Take care not to overlook the space between wget and the following URL, or any other character for that matter!

Now execute

unzip trivia.zip

to create a folder called trivia. You no longer need the ZIP file, so you can execute

rm trivia.zip

and respond with “y” followed by Enter at the prompt to remove the ZIP file you downloaded.

Now type

cd trivia

followed by Enter to move yourself into (i.e., open) that directory. Your prompt should now resemble the below.

trivia/ $

If all was successful, you should execute

ls

and you should see an index.html file and a styles.css file.

If you run into any trouble, follow these same steps again and see if you can determine where you went wrong!

Implementation Details

Design a webpage using HTML, CSS, and JavaScript to let users answer trivia questions.

• In index.html, add beneath “Part 1” a multiple-choice trivia question of your choosing with HTML.
  • You should use an h3 heading for the text of your question.
  • You should have one button for each of the possible answer choices. There should be at least three answer choices, of which exactly one should be correct.
• Using JavaScript, add logic so that the buttons change colors when a user clicks on them.
  • If a user clicks on a button with an incorrect answer, the button should turn red and text should appear beneath the question that says “Incorrect”.
  • If a user clicks on a button with the correct answer, the button should turn green and text should appear beneath the question that says “Correct!”.
• In index.html, add beneath “Part 2” a text-based free response question of your choosing with HTML.
  • You should use an h3 heading for the text of your question.
  • You should use an input field to let the user type a response.
  • You should use a button to let the user confirm their answer.
• Using JavaScript, add logic so that the text field changes color when a user confirms their answer.
  • If the user types an incorrect answer and presses the confirmation button, the text field should turn red and text should appear beneath the question that says “Incorrect”.
  • If the user types the correct answer and presses the confirmation button, the input field should turn green and text should appear beneath the question that says “Correct!”.

Optionally, you may also:

• Edit styles.css to change the CSS of your webpage!
• Add additional trivia questions to your trivia quiz if you would like!

Walkthrough

Hints

• Use document.querySelector to query for a single HTML element.
• Use document.querySelectorAll to query for multiple HTML elements that match a query. The function returns an array of all matching elements.

Testing

No check50 for this lab, as implementations will vary based on your questions! But be sure to test both incorrect and correct responses for each of your questions to ensure that your webpage responds appropriately.

Run http-server in your terminal while in your lab8 directory to start a web server that serves your webpage.

How to Submit

1. Download your index.html and styles.css files by control-clicking or right-clicking on the file in your codespace’s file browser and choosing Download.
2. Go to CS50’s Gradescope page.
3. Click “Lab 8: Trivia”.
4. Drag and drop your index.html and styles.css files to the area that says “Drag & Drop”. Be sure they have those exact filenames! If you upload a file with a different name, the autograder likely will fail when trying to run it, and ensuring you have uploaded files with the correct filenames is your responsibility!
5. Click “Upload”.

You should see a message that says “Lab 8: Trivia submitted successfully!”