要使用公共方法创建JavaScript类,我会执行以下操作:
function Restaurant() {}
Restaurant.prototype.buy_food = function(){
// something here
}
Restaurant.prototype.use_restroom = function(){
// something here
}
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这样我班级的用户可以:
var restaurant = new Restaurant();
restaurant.buy_food();
restaurant.use_restroom();
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如何创建一个可由buy_food和use_restroom方法调用的私有方法,但不能由类的用户创建外部方法?
换句话说,我希望我的方法实现能够:
Restaurant.prototype.use_restroom = function() {
this.private_stuff();
}
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但这不应该奏效:
var r = new Restaurant();
r.private_stuff();
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我如何定义private_stuff为私有方法,所以这两个都适用?
我已经阅读了Doug Crockford的几次写法,但看起来似乎不能通过公共方法调用"私有"方法,并且可以在外部调用"特权"方法.
所以我有这两个例子,来自javascript.info:
例1:
var animal = {
eat: function() {
alert( "I'm full" )
this.full = true
}
}
var rabbit = {
jump: function() { /* something */ }
}
rabbit.__proto__ = animal
rabbit.eat()
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例2:
function Hamster() { }
Hamster.prototype = {
food: [],
found: function(something) {
this.food.push(something)
}
}
// Create two speedy and lazy hamsters, then feed the first one
speedy = new Hamster()
lazy = new Hamster()
speedy.found("apple")
speedy.found("orange")
alert(speedy.food.length) // 2
alert(lazy.food.length) // 2 (!??)
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从示例2开始:当代码到达时 …