AP CSP Javascript

Why do we write functions?

I. Make our code easier to understand by giving a readable name to a group of instructions II. Avoid writing repeated code III. Make our code reusable

When we put a variable between parenthesis, what is it called?

In the following function printThreeTimes:

function printThreeTimes(word){

println(word);

println(word);

println(word);

}

What is the parameter of the function?

On which line is the "call" to the function doubleNumber on the video? (video: 4:50 )

What would I get if I called doubleNumber(10); ? (video: 5:01 )

After you watched all the video, Define the printNumbers function that takes three integers and print them in given order

function printNumbers(two, one, zero){

println(two);

println(one);

println(zero);

}

Call printNumbers function whenever printNumberBtn is clicked (hint:onEvent("printNumberBtn", "click", function(){ call functions here } );

var zero =0;

var one=1;

var two= 2;

printNumbers(zero, one, two);

What will be displayed on the screen?

Revise the printNumbers function to print given parameters in below order.

function printNumbers(two, one, zero){

println(two);

println(zero);

println(zero);

println(one);

}

Revise the code inside printNumberBtn click event function as below.

printNumbers(12, 17, 65);

What will be displayed on the screen?

“It’s a bird! It’s a plane! No, it’s Superman!”

If it’s not a bird and it’s not a plane, it must be Superman.

We want to write a function isSuperman that takes in two boolean parameters isBird and isPlane and returns true if it is in fact Superman, not a bird and not a plane, and false otherwise.

Which of the following functions is the correct implementation of isSuperman?

True or False: Functions must have parameters.

How many parameters does the function sum use?

What would get printed if we added the code,

sum(4, 3); ?

Revise your doubleNumber() function to return value instead of printing it.

Replace all code inside doubleNumberBtn to below segment.

var numApples=4;

var twiceAsMany=doubleNumber(numApples);

println("Before : "+numApples);

println("After : "+twiceAsMany);

Will will be printed when this code is run?

What happens if you try to print a function call when the function doesn't have a return value?

console.log( printNumbers(13,15,17) );

console.log ( sum(13,15,17) );

Code along with the video3 and revise the function doubleNumber to return a value.( video:2:15)

What happens if you try to call the function with a return value like below?

doubleNumber(6);

randomNumber(1,10);

Revise doubleNumber(x) function and call it inside doubleNumberBtn as shown below.

What is printed on the display?

List 3 things you have discovered today.