call example, used for prototype definition

call example, used for prototype definition

by william jiang

JavaScript

function MyObject(name, message) {
    this.name = name.toString();
    this.message = message.toString();
}

(function () {
    this.getName = function () {
        return this.name;
    };
    this.getMessage = function () {
        return this.message;
    };
}).call(MyObject.prototype);

var mo = new MyObject('william', 'queue, stack and heap');
alert(mo.getName()+', ' +mo.getMessage());

///////////////////////

// Shape - superclass
function Shape() {
    this.x = 0;
    this.y = 0;
}

// superclass method
Shape.prototype.move = function (x, y) {
    this.x += x;
    this.y += y;
    console.info('Shape moved.');
};

// Rectangle - subclass
function Rectangle() {
    Shape.call(this); // call super constructor.
}

// subclass extends superclass
Rectangle.prototype = Object.create(Shape.prototype);
Rectangle.prototype.constructor = Rectangle;

var rect = new Rectangle();

console.log('Is rect an instance of Rectangle? ' + (rect instanceof Rectangle)); // true
console.log('Is rect an instance of Shape? ' + (rect instanceof Shape)); // true
rect.move(1, 1); // Outputs, 'Shape moved.'