JavaScript Functions Worksheet

Question 1

What is a function, and why would you ever want to use one in your code?

A function is a block of code that performs a specific function/task. They are re usable so you are able to perform them more than once.

Question 2

What do you call the values that get passed into a function?

They are called arguments.

Question 3

Do all functions return a value? (Note: this is a bit of a trick question - make sure to ask me about this in class.)

Not all of them, if you have one that is undefined, it will return as "undefined"

Question 4

What is the 'body' of a function, and what are the characters that enclose the body of a function?

The body of a function is what is to be executed when the function is called upon.

Question 5

What does it mean to 'call', or 'invoke' a function (note that 'calling' and 'invoking' a function mean the same thing)?

To call or invoke a function means to execute the function by requesting it to perform its defined task.

Question 6

If a function has more than one parameter, what character do you use to separate those parameters?

When a function has more than one parameter, you use a comma.

Question 7

What is the problem with this code (explain the syntax error)?


function convertKilometersToMiles(km)
    return km * 0.6217;
                }

This is missing the opening curly brace. Indicated by the red ending curly brace in VS Code.

Question 8

In the code below, there are two functions being invoked. Which one returns a value? Explain why you know this.


const name = prompt("Enter your name");
alert("Hello " + name + "!");

The prompt function will return a value. It will return the text entered by the user.

Coding Problems

Always test your work! Check the console log to make sure there are no errors.