Web service for C# dll

Does anyone have an example of setting up a web service of a C# dll. I have been through the example of a C dll in the documentation but I do not know how to extrapolate this to C#. For example:
1. What should the namespace be called?
2. How does one identify the class and the method to be called?
3. Are the names used in the dataview important? If so, how?
Thanks in advance
1. What should the namespace be called?
2. How does one identify the class and the method to be called?
3. Are the names used in the dataview important? If so, how?
Thanks in advance