How to auto like facebook page from other site?

Question

On the facebook page,we can click the like button to like the page. How can we use any api or plugin to realize from other site?

Answer 1

You can not automatically like an object for a user nor can you present like via the APIs. This prevents anyone "secretly" having users like pages / objects.

The solution is to embed a like button to your page and give users a clear reason to use it [sell the benefit of liking your page]. You can run a separate version for individual pages, objects or just an aggregate button for all of your site via the data-href element.

http://developers.facebook.com/docs/reference/plugins/like/

Answer 2

You can check if a user has liked your page using:

FB.api('/me/likes', function(response) {
  console.log(response);
});

Loop through the response and look for your page ID.