Javascript综合使用

JavaScript中也可以实现私有属性，而且JavaScript也能像C++和Java一样支持基于类的继承方法。为了展示这些是怎样实现的，下面说明如何转换前面使用Vehicle、SportsCar和CementTruck对象的例子，从而使用信息隐藏和继承的新模式。代码清单5-5列出了新的对象定义。

代码清单5-5 classicalInheritance.js

function Vehicle() {

var wheelCount = 4;

var curbWeightInPounds = 4000;

this.getWheelCount = function() {

return wheelCount;

}

this.setWheelCount = function(count) {

wheelCount = count;

}

this.getCurbWeightInPounds = function() {

return curbWeightInPounds;

}

this.setCurbWeightInPounds = function(weight) {

curbWeightInPounds = weight;

}

this.refuel = function() {

return "Refueling Vehicle with regular 87 octane gasoline";

}

this.mainTasks = function() {

return "Driving to work, school, and the grocery store";

}

}

function SportsCar() {

this.refuel = function() {