JavaScript Functions Worksheet

Question 1

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

It is used to "duplicate" code. It will run the same code as many times as you call it.

Question 2

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

They are called paramiters.

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.)

Yes? But you can't see it unless you use the return keyword.

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 whatever is placed inside the curly braces {}.

Question 5

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

When you put your function to use.

Question 6

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

You would use a comma.

Question 7

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


function convertKilometersToMiles(km)
    return km * 0.6217;
}

There is no opening 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 + "!");

Prpmpt returns the name value.

Coding Problems

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