Objects Lab

Learning Goals

• Create an Object
• Perform operations on an Object

Introduction

We covered the concepts of Objects in JavaScript. Now it's time to put the concepts into practice.

If you haven't already, fork and clone this lab into your local environment. Navigate into its directory in the terminal, then run code . to open the files in Visual Studio Code.

Instructions

Follow the steps below, running npm test as you go to get additional information from the tests. Don't forget to run npm install first!

Let's say we are working on a program that will keep track of a company's employees. We want to store each employee as an Object. We're starting small, so to begin with we'll only keep track of the employee's name and street address.

To start, assign an employee variable to an Object containing name and streetAddress keys; you can use whatever values you like. Use literal syntax to create your Object. Various updates will be applied to this variable (destructively and non-destructively) in this lab.

Once you've initialized the employee Object, you'll need to create the following four functions:

• updateEmployeeWithKeyAndValue(): this function should take in three arguments: an employee Object, a key and a value. This function should not mutate the employee; it should return a new Object that has an updated value for the key passed in. Hint: use the spread operator!
• destructivelyUpdateEmployeeWithKeyAndValue(): this function should work the same as updateEmployeeWithKeyAndValue() but it should mutate the employee Object passed in.
• deleteFromEmployeeByKey(): this function should take in a employee Object and a key. It should delete the property with that key from the employee Object. This should not mutate the original employee Object; it should return a new Object that doesn't include the identified key-value pair. Hint: use the spread operator!
• destructivelyDeleteFromEmployeeByKey(): this function should work the same as deleteFromEmployeeByKey() but it should mutate the employee Object.

As you work on your functions, be sure to think about when to use dot notation vs. bracket notation.

After you have all the tests passing, remember to commit and push your changes up to GitHub, then submit your work to Canvas using CodeGrade.

Conclusion

In this lab, we practiced creating an Object and performing operations on it.

Resources

• MDN: Object