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/*
Learn How to Program Using Any Web Browser
by Harold Davis
Apress CopyRight 2004
ISBN: 1590591135
*/
<HTML>
<HEAD>
<TITLE>Instance method demo</TITLE>
</HEAD>
<BODY>
<H1>
<SCRIPT>
function Rectangle(height, width){
// constructor function
this.height = height;
this.width = width;
}
// create the function
function calc_Area () {
return this.height * this.width;
}
// turn the function into an object method
Rectangle.prototype.calcArea = calc_Area;
// instantiate the object
var theRectangle = new Rectangle (3, 5);
// set an instance property
theRectangle.width = 10;
// call and display the instance properties and method return
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>
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