I'd like to post messages to a group wall without asking user for login information -I'd like to do it programmatically, I can use my user/pass if necessary-.
¿Is it possible to do this without showing the user the login screen?
Note: I'm working with Facebook C# SDK (http://facebooksdk.codeplex.com/) under ASP.NET.
Thanks
No you cannot do this. Facebook prevents this sort of behavior to prevent spamming on peoples walls from fake accounts. You will always have to go through the initial login procedure AT LEAST ONCE.
However, if you get an offline access token for someone then you could continue to make posts from them when they are not logged in. Keep in mind that Facebook limits you to 600 posts per minute.
来源：https://stackoverflow.com/questions/4344666/how-to-login-to-facebook-using-the-facebook-c-sharp-sdk