问如何在我的网站上添加facebook分享按钮？

EN

<script src='http://connect.facebook.net/en_US/all.js'></script>
    <p><a onclick='postToFeed(); return false;'><img src="images/fb.png" /></a></p>
    <p id='msg'></p>

    <script> 
      FB.init({appId: "338334836292077", status: true, cookie: 

true});

      function postToFeed() {

        // calling the API ...
        var obj = {
          method: 'feed',
          redirect_uri:'https://www.facebook.com/cryswashington?fref=ts',
          link:'https://developers.facebook.com/docs/reference/dialogs/',
          picture: 'http://fbrell.com/f8.jpg',
          name: 'Facebook Dialogs',
          caption: 'Reference Documentation',
          description: 'Using Dialogs to interact with users.'
        };

        function callback(response) {

        document.getElementById('msg').innerHTML = "Post ID: " + response['post_id'];
        }

        FB.ui(obj, callback);
      }

    </script>