|
<HTML>
<HEAD>
<TITLE>Instance method demo</TITLE>
</HEAD>
<BODY>
<H1>
<SCRIPT>
// constructor function
function Rectangle(height, width){
this.height = height;
this.width = width;
}
function getArea () {
return this.height * this.width;
}
// turn the function into an object method
Rectangle.prototype.calcArea = getArea;
var theRectangle = new Rectangle (3, 5);
theRectangle.width = 10;
document.write("The rectangle instance height is: " + theRectangle.height + "<br>");
document.write("The rectangle instance width is: " + theRectangle.width + "<br>");
document.write ("The calcArea method returns: " + theRectangle.calcArea());
</SCRIPT>
</H1>
</BODY>
</HTML>
|