hai ,
i would like to know how to design a interface using C#.net connected via serial port?? can you explain with an example?????????? or any link which leads to the tutorial of it????????? please help me its important for me......................................... please help me..................

 

What devices will this interface connect? Serial communications have been around for many years now, and generally do not present a challenge to make work. Software merely opens a communication port and sends/receives data. It plays no part in the actual interface, which is all hardware.

If C# can open a port for input/output, then the software should present no problem. Your C# manual should have the instructions and examples in it.