Is it possible to detect when someone clicks the like button \"and before the like action really occurs\", i.e. same as onSubmit JS event, it detects when the user submit th
You can subscribe to an event that will notify you when the user likes something - however this will fire after the action. This is documented at: http://developers.facebook.com/docs/reference/javascript/FB.Event.subscribe/
An example would be:
FB.Event.subscribe('edge.create', function(response) { alert('You liked the URL: ' + response); /* check the response here to see if it's your URL */ });
You could attempt to intercept the action but why would you want to wait to add the meta? Do you mean the open graph headers? Facebook scrapes these every 24-hours, not for each unique like event. Also it would most likely be against Facebook's terms to intercept/alter the like action, as you'd be interfering with their established and expected guidelines.