说明： 本教程部分中将简单讨论COM和VB的相关内容，这包括类的创建，以及如何将类转换成一个实际对象。虽然，这里的内容太过简单，但却是以后COM编程的基础。 (part of the handbook will be a brief discussion on COM and VB-related content, including the creation category, and how to type into a real object. Although the content here is too simple, but it is beyond COM programming foundation.)
