将变量作为IIFE中的属性返回 [英] Return a variable as a property in an IIFE

问题描述

我试图在IIFE初始化后返回一个变量集作为属性。问题是如果我直接绑定变量，我得到一个空对象。如果我通过函数绑定它，我得到我想要的结果。

I am trying to return a variable set after the initialization of an IIFE as a property. The issue is if I bind the variable directly, I get an empty object. If I bind it through a function, I get my desired result.

var Application = (function(){

    var localInformation = {};

    function init(){
        localInformation = _demoApiCall();
    }

    function _demoApiCall(){
        // Pretend this method isn't here, and returns a complex object
        return {
            name: "Demo"
        }
    }

    function doWork(){
        // localInformation is properly structured here if called
    }

    return {
        Init: init,
        DoWork: doWork,
        InfoProp: localInformation, // returns {}
        InfoMethod: function(){
            return localInformation; // returns {name:"demo"}
        }
    }

})();

Application.Init();

console.log(Application.InfoProp);
console.log(Application.InfoMethod());

最初的c之后在文档准备好的所有 Application.Init（）上，该示例仅在我调用 var inf = Application.InfoMethod（），但如果我可以打电话给 var info = Application.InfoProp ，那就更清洁。

After initially calling Application.Init() on document ready, the example will only work if I call var inf = Application.InfoMethod(), however it would be much cleaner if I could call var info = Application.InfoProp.

我'我试图阅读JS闭包，但没有得到任何关于为什么没有适当的私有变量引用的信息。

I've tried to read up on JS Closures, but haven't gotten any information into why there would be no proper reference to the private variable.

推荐答案

我想你的意思是在你的退货对象中写 localInformation 。

I guess you meant to write localInformation in your returned object.

问题是你是将 localInformation 变量名称重新分配给新对象。

The problem is that you are re-assigning the localInformation variable name to a new object.

localInformation = _demoAPICall()

意味着你的 InfoProp 属性指向 localInformation （空对象）的初始值，而在函数内，您获得 localInformation的最新值。

Meaning that your InfoProp property points to the initial value of localInformation (the empty object), while within the function, you get the latest value of localInformation.

您有两种选择：

1）扩展现有对象，而不是将变量名称分配给新一个：

1) Extend the existing object instead of assigning the variable name to a new one:

extend(localInformation, _demoApiCall())

你可以使用jQuery的扩展，或者来自lodash的扩展，或任何其他实现都可以。

You cann use jQuery's extend, ot the one from lodash, or any other implementation will do.

2）使用getter方法

2) use a getter method

return {
  Init: Init,
  get InfoProp () { return information },
  ....
} 

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