about csharp wrapper

If you are talking about C# Wrapper within Advanced Samples, then you can find relevant information on a product page or contact Open Cascade for more details. From description:

This component not only provides the ready to use wrappers for the most used part of Open CASCADE Technology high-level API, but also describes the methodology of wrapping

So, no, the sample does not wrap all the functions in OCCT framework, but it wraps a considerable amount of them, and also provides a description and helpers for easily wrapping more OCCT classes.
Practically speaking, OCCT is a very huge C++ framework, not everything in C++ could be (easily) wrapped into C#, considering limitations of the language itself and particular wrapping approach, and not everything is reasonable to wrap.