Hello,
Ok, I would recommend you to try using Kentico's API to handle this. Please download the
API Reference and then take a look at the class:
CMS.SocialNetworking where you can find some methods to achieve this, e.g. for Twitter:
CMS.SocialNetworking ► TwitterProvider ► PublishTweet(String, String, String, String, String)
(more details about the paramateters in the API ref).
I hope this will help you.
Best regards,
Martin Danko