说明：   VB.net的串口通讯支持总是让人觉得有所不足，在使用VB6的MsComm32.ocx时，很多人都会在VB.net的开发中觉得很困扰。 这里讲述的VB.net串口通讯类使用native代码，并且它是通API调用实现的，你会发现VB.net的串口通讯就是这么简单。
(VB.net serial communications support always make people feel inadequate. use VB6 MsComm32.ocx, many people in VB.net development feels very frustrated. Here on the VB.net serial communications using native code, and it is- API calls to achieve, and you will find VB.net Serial communication is as simple as that.)