JavaScript的自定义索引访问 [英] Javascript custom index accessor

问题描述

在C＃中，您可以创建像这样一个自定义的索引

In c# you can create a custom indexer like so

public object this[string name]
    {

    }

我与它有一个小部件，需要对象的阿雷作为属性称为标签，像这样一个JavaScript控件库工作

I'm working with a javascript widget library which has a widget that takes an aray of objects as a property called labels like so

new  Thingy({
      labels: [{value:1, text:"my label"},[{value:2, text:"my next label"}]
      });

问题是，你必须提前计划确切地知道所有值都将需要一个标签。例如，在上面的例子中，我知道该标签将是值1和2。但是，如果我不知道是什么值可能是，我想能够基于价值它动态地创建文本尝试访问

The problem is that you have to plan ahead to know exactly what all the values are that will need a label. For instance, in the example above, i know that the labels will be for values 1 and 2. But if I don't know what the values might be, i would like to be able to dynamicly create the text based on the value it tries to access

所以当库内部尝试访问：

so when the library internally tries to access:

this.labels[n].text

我想this.labels [N]做这样的事情。

I would like this.labels[n] to do something like

function(n){return {text: "label for " + n};}

这是可能的JavaScript语言的范围内？

Is this possible within the bounds of the javascript language?

推荐答案

您可以得到的 ES6代理在最新的Chrome和编写一个处理像在C＃中，但它不会与旧的浏览器兼容。

You can get es6 proxies in latest Chrome and write a handler like in C#, but it won't be compatible with older browsers.

同时，我建议把一个 getLabel（）方法在 Thingy.prototype 。

Meanwhile I suggest putting a getLabel() method on a Thingy.prototype.

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