用户单击“开始”，然后默数 10 秒。10钟后单击停止，看看他默数时间的误差是多少。 需控件：Command1、Command2、Label1、Label2 所有控件采用默认设置，复制下面的代码，粘贴到窗体的代码窗口，运行即可-Users click the " Start" , then silently count 10 seconds. 10 minutes after the click to stop, take a look at him and silently count the time the error is. ' Need to control: Command1, Command2, Label1, Label2'　all the controls using the default settings, copy the following code and paste it into the form' s code window, you can run