sir like below we can do
<asp:HyperLink ID="HyperLink1" runat="server" NavigateUrl="http://www.facebook.com/dialog/send? app_id=123050457758183& name=Facebook%20Dialogs& link=http://developers.facebook.com/docs/reference/dialogs/& redirect_uri=http://www.royalsikkim.com/">Click Me</asp:HyperLink>
here Click Me(u can make as send button) in which click it show facebook send dialog.
sir plz let me know any other gud option is their.