How to extend expiry of a long-live token in facebook graph api

问题

I am having a issue here, I have a long-live access token, I dont want this token to expire after 60 days, I Understand that to extend the life time of a long-live token we need to fire a query below using shot-live token..

GET /oauth/access_token?  
   grant_type=fb_exchange_token&           
   client_id={app-id}&
   client_secret={app-secret}&
   fb_exchange_token={short-lived-token} 

But short lived token expires in hours .. So i cant use the same short-live token again to request for extending life span of long-live token . Is there any way i can do it programaticaly, I dont want user to come in picture any time once he has created short-lived token in the beggining... any help is appreciated..

Regards Sunil

来源：https://stackoverflow.com/questions/19223904/how-to-extend-expiry-of-a-long-live-token-in-facebook-graph-api