socket programming in C#

Will the firewall which is already running allow this kind of behavior from an executable?

yes The functionality which i want like the functionality in firewall .

Closing or opening a port? Are you speaking about firewall -like functionality?

Thank you Simon... I mean in my question : I want to control the port such as (80,25,...) via c# that is i can open or closed this port . suppose when i closed port 80(http) i cann't open any web page and i think i do that by socket classes in C# but really i donn't know how i can to do this?????????? I hope you understand what i need thanks

Hi I don't really understand your question. Please try to explain. Simon