如何获取 JavaScript 哈希表计数？
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How to get JavaScript hash table count?
提问by rsk82
Possible Duplicate:
Length of Javascript Associative Array
可能的重复：
Javascript 关联数组的长度
hash_table = {a: 131, b: 222, c:313}
The length method is not working of course since it will be confused with a key.
length 方法当然不起作用，因为它会与键混淆。
So how do I do it?
那么我该怎么做呢？
回答by qiao
Object.keyswill return all the keys in the object as a list, then use length to get the length.
Object.keys将对象中的所有键作为列表返回，然后使用长度来获取长度。
example:
例子：
Object.keys(hash_table).length
NOTE that this is ECMA 5 and may not be available in some browsers. see https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Object/keysfor full document.
请注意，这是 ECMA 5，可能在某些浏览器中不可用。有关完整文档，请参阅https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Object/keys。
回答by simonecampora
var count = 0;
for ( property in hash_table ) count++;
