How to implement New facebook SDK all.js in our application

I am new to Facebook Implementation. In my previous facebook implementation I have a Function which is Using old Featureloader.js

FB.Facebook.apiClient.users_hasAppPermission("email",function(has){
              if (has == 0) {
                 FB.Connect.showPermissionDialog("email", function(granted){
          开发者_运维知识库         popupFbSignUp(); 
                 }); 
              }
              else {
                 popupFbSignUp(); 
              }
            });

Have you looked over the docs? https://developers.facebook.com/docs/reference/javascript/

This is also probably relevant for you: https://developers.facebook.com/docs/reference/javascript/FB.login/

There is a full working example here: https://developers.facebook.com/blog/post/525/