Facebook share button?

Question

JavaScript

1. I need such a button to share

2. I need to know if the user has published a post on the wall or not.
Therefore, the standard buttons do not suit me.
Fb made an api but made an incomprehensible description of this api.
For example, it is written here

FB.ui(
  {
    method: 'share',
    href: 'https://developers.facebook.com/docs/',
  },
  // callback
  function(response) {
    if (response && !response.error_message) {
      alert('Posting completed.');
    } else {
      alert('Error while posting.');
    }
  }
);

But there is no information where the FB object is located anywhere. That is, such a code will cause an error FB.ui is not defined
Since VK and classmates are the absolute opium of fb, nothing is explained there in the same way.

Answer 1

description of how to connect and initialize the FB object: https://developers.facebook.com/docs/javascript/qu...

<script>
  window.fbAsyncInit = function() {
    FB.init({
      appId            : 'your-app-id',
      autoLogAppEvents : true,
      xfbml            : true,
      version          : 'v3.1'
    });
  };

  (function(d, s, id){
     var js, fjs = d.getElementsByTagName(s)[0];
     if (d.getElementById(id)) {return;}
     js = d.createElement(s); js.id = id;
     js.src = "https://connect.facebook.net/en_US/sdk.js";
     fjs.parentNode.insertBefore(js, fjs);
   }(document, 'script', 'facebook-jssdk'));
</script>

PS. I am sure that both VK and OK have detailed documentation. just dig deeper :)