public void ChooseSubject(string subjectName)
{
//外观模式，将后台系统封装在这里面，客户端要调用也是统一调用外观，不会直接请求后台系统
var validateSubject = new ValidateChooseSubject();
var chooseSubject = new ChooseSubject();
var notify = new SubjectNotify();
//判断是否选满
var isFull = validateSubject.IsFull(subjectName);
//没选满，选课
if (!isFull)
{
chooseSubject.Choose(subjectName);
}
//选课完毕，发送通知
notify.Notify(subjectName, !isFull);
}
private static void TestNormal()
{
//常规选课：
var validateSubject = new ValidateChooseSubject();
var chooseSubject = new ChooseSubject();
var notify = new SubjectNotify();
var subjectName = "轮滑";
//判断是否选满
var isFull = validateSubject.IsFull(subjectName);
//没选满，选课
if (!isFull)
{
chooseSubject.Choose(subjectName);
}
//选课完毕，发送通知
notify.Notify(subjectName, !isFull);
}