javascript - How do I get the counter of a google plus +1 button?

Question

I have added a google +1 button to a website, but I want to get it's counter so i can do some math over it. is it possible to enter the iframe created by the standard method of creating the +1 button or do I need to make some adjustment?

<script type="text/javascript" src="https://apis.google.com/js/plusone.js"></script>
<g:plusone></g:plusone>

I've tried this link:1 , but this is not very accurate

Answer 1

If you can access curl/file_get_contents/readfile/wget or some way to fetch an external URL, this is quite simple.

Load the following URL: https://plusone.google.com/_/+1/fastbutton?url=URLENCODED_URI (UPDATED URL, see note below *)

URLENCODED_URI is the site you wish to know the number of +1's for, e.g. http://www.google.com (http%3A%2F%2Fwww.google.com)

For example, fetch the URI https://plusone.google.com/_/+1/fastbutton?url=http://www.google.com/ (UPDATED URI) and locate the first occurance of window.__SSR = {'c': 32414.0 ,'si'. Preferably use regexp for this, but I'll leave the implementation to you and your chosen programming language (server side or client side).

The float number following 'c' is the number of +1's the site have. For google.com this is 32,414. Don't worry about the float, you can safely convert it to an integer.

* UPDATE: The URL has been updated as the old URL started to 404. Remember, this is expected as this is an unofficial method. There exist no official method (yet).