How to get JavaScript hash table count?

javascript hashtable
rsk82 picture rsk82 · Jan 2, 2012 · Viewed 36.9k times · Source

Possible Duplicate:
Length of Javascript Associative Array 

hash_table = {a: 131, b: 222, c:313}

The length method is not working of course since it will be confused with a key.

So how do I do it?

Answer

qiao picture qiao · Jan 2, 2012

Object.keys will return all the keys in the object as a list, then use length to get the length.

example: 

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/keys for full document.

Related questions

How to do associative array/hashing in JavaScript

I need to store some statistics using JavaScript in a way like I'd do it in C#: Dictionary<string, int> statistics; statistics["Foo"] = 10; statistics["Goo"] = statistics["Goo"] + 1; statistics.Add("Zoo", 1); Is there an Hashtable or something like Dictionary&…

Read More
How do I encode a JavaScript object as JSON?

Is there a good way to encode a JavaScript object as JSON? I have a list of key value pairs...where the name is from a checkbox, and the value is either true or false based on whether the box …

Read More
Hash table in JavaScript

I am using a hash table in JavaScript, and I want to show the values of the following in a hash table one -[1,10,5] two -[2] three -[3, 30, 300, etc.] I have found the following code. It works for the following …

Read More