JavaScript Functions Worksheet

Question 1

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

Functions allows you to break down complex tasks into smaller, manageable units, making your code more organized, readable, and maintainable. Once you define a function, you can call it from anywhere within the code as many times as needed, avoiding code duplication.

Question 2

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

Parameter

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, it does not return a value until you have declare or 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 a function is a statement that defines the function and enclosed in 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)?

It means to execute its statement and return the value in the function.

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;
}

A missing curly brace after the parameter.

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 + "!");

Prompt pops up a box to enter your name and alert value takes what the user has input from the prompt text.

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.