I want to POST a data as JSON to the controller

in javascript, the data is an array, for example, a = [1,2]

then I POST, say

```
$.post('user/data', {'data' : a})

```

in the user controller, I get the data from params.

However, when I retrieve params[:data], I got a hash:

```
{"0"=>1, "1"=>2}

```

rather then an array!

so I have to convert the hash into an array manually.

Is there a method to pass the exact array to the controller?