JavaScript Functions Worksheet

Question 1

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

A function acts as a keyword with the an ability to execute a grouping of pre-written code.

Question 2

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

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.)

No, not all programmed functions are required to return a value

Question 4

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

The body of the function are all statements (operations) that take place.
The body of the function is contained, or enclosed, within curly brackets ({ })

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 a function is to execute the commands later on within the order of the code.
(A function is pre-programmed once and only in use the next time it is invoked)

Question 6

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

A commma (,)

Question 7

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


function convertKilometersToMiles(km)
    return km * 0.6217;
}

The opening curly-bracket to encapsulate the body is missing after the parenthesis (km)

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 is an included function in JavaScript (source code) that returns a value to the chosen
variable "name".

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.