JavaScript Functions Worksheet

Question 1

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

Functions allow you to execute a group of statements multiple times in a program without having to repat code. This makes the program more efficient as well as the tasking of programming itself by not having to repeat the same lines of code over and over.

Question 2

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

The values that are passed into a function are called parameters.

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.)

Technically all functions return something.

Question 4

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

The code that goes between the curly braces is known as the body, these are the statements that are going to be executed when the function is called.

Question 5

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

When a function is executed it is being called /invoked.

Question 6

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

A comma.

Question 7

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


function convertKilometersToMiles(km)
    return km * 0.6217;
}

It is missing the beginning curly bracket.

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 for the name constant. It requires input to determine the output value or "return value".

Coding Problems

Coding Problems - See the 'script' tag below this h3 tag. You will have to write some JavaScript code in it.

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