访问权限

// static: is callable on a class even when no instance of the class has been created
public static void MyMethod()

// virtual: can be called or overridden in an inherited class
public virtual  void MyMethod()

// internal: access is limited within the current assembly
internal  void MyMethod()

//private: access is limited only within the same class
private  void MyMethod()

//public: access right from every class / assembly
public void MyMethod()

//protected: access is limited to the containing class or types derived from it
protected void MyMethod()

//protected internal: access is limited to the current assembly or types derived from the containing class.
protected internal void MyMethod()