Today's assignment is to practices some parts of JavaScript you've learnt so far to create a little text-based bot which you can use to order pizza on your computer.
Follow the tasks below and write your bot code in code/pizzabot.js. You can open code/index.html in the browser to use and test the bot.
The bot you'll build is a fake ordering system which will use alert() and prompt() to allow the user to input orders, and the bot to send output. Read up on how to use them before you continue.
Before you start writing your "bot", there's a few things you should know about your pizzeria:
- Your pizzeria only serves 3 different pizzas right now; Vegetarian, Hawaiian and Pepperoni.
- All the pizzas have the same price - 80 SEK.
- Because of the popularity of your pizzeria, and long queues, you can only order multiple pizzas of the same sort.
To start you off, we've defined 4 variables in code/pizzabot.js which you'll use throughout the rest of this assignment:
const vegetarian = "Vegetarian Pizza"
const hawaiian = "Hawaiian Pizza"
const pepperoni = "Pepperoni Pizza"
const pizzaPrice = 80
In code/pizzabot.js, you can start coding the bot interaction. The first step is to greet a new customer.
Use alert() to print the message "Hey! Happy to serve your pizza. On our menu we have X, Y and Z".
Use the variables vegetarian, hawaiian and pepperoni to replace X, Y and Z in the message so that it reads "Hey! Happy to serve your pizza. On our menu we have Vegetarian Pizza, Hawaiian Pizza and Pepperoni Pizza"
Use prompt() to ask the user which pizza they want. The message in the prompt should read Enter the name of the pizza you want to order today.. Their response should be stored in a new variable called orderName.
Next, ask the user (with another prompt()) how many they'd like: How many of X do you want?. X should be replaced with the orderName variable so that it if I ordered "Hawaiian Pizza" it would read "How many of Hawaiian Pizza do you want?". As before, the response from this prompt should be stored in a variable, this time called orderQuantity
Calculate the total price of the order using the orderQuantity and pizzaPrice variables and store it in a variable called orderTotal. Use an alert to tell the user: Great, I'll get started on your X right away, it will cost Y kr (where X should be replaced by the orderName variable and Y should be replaced by the orderTotal variable).
For example, if I ordered 3 Hawaiian pizzas, the message should read: "Great, I'll get started on your Hawaiian Pizza right away, it will cost 240 kr"
We want you to add three conditionals statements (if-statements) to your program to improve it.
When the user enters the orderName prompt, add an if-statement to check if the input text matches any of the pizza name variables (vegetarian, hawaiian, pepperoni).
Before you print the final Great, I'll get started on your X right away, it will cost Y kr message to the user, calculate the cooking time based on these rules and add it to the message:
- 1-2 pizzas:
The pizzas will take 10 minutes. - 3-5 pizzas:
The pizzas will take 15 minutes. - 6+ pizzas:
The pizzas will take 20 minutes.
For example, if I ordered 3 Hawaiian pizzas, the message should now read: "Great, I'll get started on your Hawaiian Pizza right away, it will cost 240 kr. The pizzas will take 15 minutes."
Finally, clean up your code by moving some code into functions and then calling that function when needed.
The functions should all reflect the tasks we've completed so far. So, the functions should be:
checkOrderName()which should take theorderNamevariable as an argument and returntrueorfalseif the pizza is on the menu or not.totalCost()which takesorderQuantityas an argument and returns the total cost for the order.cookingTime()which takesorderQuantityand returns the number of minutes it will take to finish the order.
As always, when you're done, submit a pull request on GitHub (from your repository into the technigo one) for review. Read the guide on GitHub for more info on how to do this.
Learning how to think as a web developer is learning how to be an expert in problem solving. So whenever you get stuck start with step 1 and continue until problem solved.
- Google! In English, type in the error message if there is one, search within the language your're using (ie CSS, JavaScript etc).
- Ask your code buddies in your Company.
- Ask your fellow students in Slack.
- Ask Damien or David. Please note: we are part of a sharing community - share the answer with your fellows.
After completing this assignment your should:
- Be comfortable using variables
- Know some string methods to modify strings
- Understand control flow and the use of conditionals statements
- Be able to write basic functions which take arguments and return values
Done with the main task? Here's some ideas for things to continue with:
- Go to the Wikipedia Article about Hawaiian Pizza and:
- Copy the first three paragraphs. Store the text in a String
- Make your program count the number of words in the string
- Make your program count the number of times the word pineapple appears.
- Instead of having your pizzabot live in the console make a form in HTML for the input from the user, pizza type and number of pizzas. Then make your program print it's response in HTML instead.
A combination of these two examples will help you on the way: Forms submissions with JavaScript and Get Element by ID.