c# - how i can get photos in picasa album by FeedUri -

i want photos in picasa album feeduri feeduri , separate album id , write code

public actionresult detail(string feeuri)     {          int n=feeuri.lastindexof("/");         string s=feeuri.substring(n+1);         photoquery query = new photoquery(picasaquery.createpicasauri("username", s));         picasafeed feed = service.query(query);         //...           return view();     } 

but error url wrong