For example, it is possible to express that InvoiceType (type of Invoice number) cannot be subtyped, that is, no one can define a new version of InvoiceType.
比如，有可能表示InvoiceType (Invoice编号的类型)不允许子类型化，任何人都不能定义新版本的InvoiceType。
youdao
应用推荐
模块上移
模块下移
不移动