javascript - 如何在 JavaScript 中进行关联数组/散列

Question

我需要使用 JavaScript 存储一些统计信息，就像在 C# 中那样:

Dictionary<string, int> statistics;

statistics["Foo"] = 10;
statistics["Goo"] = statistics["Goo"] + 1;
statistics.Add("Zoo", 1);

有没有Hashtable或类似Dictionary<TKey, TValue>在 JavaScript 中？
我如何以这种方式存储值？

Answer 1

使用JavaScript objects as associative arrays .

Associative Array: In simple words associative arrays use Strings instead of Integer numbers as index.

创建一个对象

var dictionary = {};

JavaScript allows you to add properties to objects by using the following syntax:

Object.yourProperty = value;

其替代语法是:

Object["yourProperty"] = value;

如果可以的话，还可以使用以下语法创建键到值对象映射:

var point = { x:3, y:2 };

point["x"] // returns 3
point.y // returns 2

You can iterate through an associative array using the for..in loop construct as follows

for(var key in Object.keys(dict)){
  var value = dict[key];
  /* use key/value for intended purpose */
}