The Essential Guide to HTML5

CHAPTER 8

Code Explanation

... = String(0);

(and it actually isn't necessary since

JavaScript will convert a number to a string in

this situation)

ctx = document.getElementById

('canvas').getContext('2d');

Set the variable to be used for all drawing

canvas1 = document.getElementById

('canvas');

Set the variable to be used for the mouse

click event handling

canvas1.addEventListener

('click',choose,false);

Set up click event handling

drawall(); Draw everything

ctx.font="bold 16pt Georgia"; Set the font to be used for the result
messages

ctx.fillStyle = "blue"; Set the color

} Close the function

function drawall() { Header for the function

ctx.clearRect(0,0,cwidth,cheight); Clear the canvas

var i; Variable for indexing

for (i=0;i<everything.length;i++) { Iterate through the everything array

everything[i].draw(); Draw the individual elements

} Close the for loop

} Close the function

Close the script element
Close the head element
Starting body tag. Set up call to the init
function