在JavaScript中存储key =>值数组的最佳方法？ [英] Best way to store a key=>value array in JavaScript?

问题描述

在javascript中存储 key =>值数组的最佳方法是什么？如何循环使用？

每个元素的键应该是一个标记，例如 {id} 或只是 id 和值应该是id的数值。

它应该是现有javascript类的元素，或者是一个可以通过可以使用jQuery。

解决方案

这就是什么一个JavaScript对象是：

  var myArray = {id1：100，id2：200，tag with spaces：300}; 
 myArray.id3 = 400; 
 myArray [id4] = 500; 
  

您可以使用 for..in loop ：<对于（myArray中的var键）{
console.log（key+ key +has value+ myArray的[键]）;
}

另请参阅：使用对象（MDN）。

在ECMAScript6中还有 Map （参见那里的浏览器兼容性表）：

• 一个对象有原型，因此地图中有默认键。这可以通过使用自ES5以来的map = Object.create（null）来绕过，但很少完成。




• 对象的键是字符串和符号，它们可以是地图的任何值。




• 当您必须手动跟踪对象的大小时，您可以轻松获得地图的大小。

What's the best way to store a key=>value array in javascript, and how can that be looped through?

The key of each element should be a tag, such as {id} or just id and the value should be the numerical value of the id.

It should either be the element of an existing javascript class, or be a global variable which could easily be referenced through the class.

jQuery can be used.

解决方案

That's just what a JavaScript object is:

var myArray = {id1: 100, id2: 200, "tag with spaces": 300};
myArray.id3 = 400;
myArray["id4"] = 500;

You can loop through it using for..in loop:

for (var key in myArray) {
  console.log("key " + key + " has value " + myArray[key]);
}

See also: Working with objects (MDN).

In ECMAScript6 there is also Map (see the browser compatibility table there):

• An Object has a prototype, so there are default keys in the map. This could be bypassed by using map = Object.create(null) since ES5, but was seldomly done.

• The keys of an Object are Strings and Symbols, where they can be any value for a Map.

• You can get the size of a Map easily while you have to manually keep track of size for an Object.

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