base.js与沙盒 [英] base.js with sandboxing

问题描述

我正在使用base.js的实现：http：//ejohn.org/blog/simple-javascript-inheritance/



I试图将其与沙盒相结合以获得私有变量。例如：

I''m using an implementation of base.js from here: http://ejohn.org/blog/simple-javascript-inheritance/

I attempted to combine this with sandboxing to get "private" variables. For example:

// Sandbox.
(function () {

var privateVar;

myClass = Class.extend({
    init: function (bindingOptions) {
        privateVar = 0;
    },

getPrivateVar: function() {
    return privateVar;
},

setPrivateVar: function(value) {
    privateVar = value;
});
})();

但是，当我尝试制作2个实例时，privateVar当然具有相同的值。例如：

However, when I try to make 2 instances, of course the "privateVar" has the same value. For example:

var class1 = new myClass();
var class2 = new myClass();
class1.setPrivateVar(5); // now both class1 and class2 report privateVar as "5"

有没有什么办法可以使用这种方法来获取私有变量，而不需要求助于this._privateField？

Is there any way to get private variables using this methodology that are scoped to the object without resorting to "this._privateField" ?

推荐答案

之后进一步的研究，这里的答案是不可能的。



参考： http://robertnyman.com/2008/10/21/javascript-inheritance-experimenting-with-syntax-alternatives-and- private-variables / [ ^ ]



原因是如果你使用我上面概述的沙盒方法，任何私有变量宣布将是圣ATIC。但是，方法可以成功隐藏和工作。

After further research, the answer here is that it isn''t possible.

Reference: http://robertnyman.com/2008/10/21/javascript-inheritance-experimenting-with-syntax-alternatives-and-private-variables/[^]

The reason is that if you use the sandboxing methodology I outlined above, any "private" variable declared will be static. Methods, however, can successfully be hidden and work.

如果你想要特定于实例的私有变量，

If you want instance specific private variables,

function ClassConstructor(...) {
var that = this;
var membername = value;
function privatememthod(...) {...}

}

你有特定于实例的私有变量membername&私有方法privatemethod。



访问外部方法：

you have instance specific private variable membername & private method privatemethod.

Access for external methods:

function ClassConstructor(...) {
var that = this;
var membername = value;
function privatememthod(...) {...}

return {
  getPrivareMember: function(){
       return membername;
  }
}
}

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