通用控件是Windows应用程序用户界面的重要组成部分，然而Windows通用控件有很多个，根据控件使用的难易程度，将控件分为几个类别，由浅入深，通过学习，读者就可以利用这些控件完成基本的Windows编程任务。(General control is an important part of the user interface of the Windows application, but there are many Windows general-purpose controls. According to the difficulty of the use of the control, the controls are divided into several categories, and the readers can use these controls to complete the basic Windows programming tasks by learning.)