Question

how to convert my C# winform program to service program ?

i need that my program will work like service (like listener)

Answer 1

A windows service doesn't have a GUI, so the sole notion of talking about converting a WinForms application with a GUI to a Windows service hardly makes sense. You may take a look at the following article about writing windows services using .NET. If you need to host some sevrice listening on a given port you may take a look at hosting a WCF service in a managed Windows service.