备忘录在 PHP 中的实现
Memento is a behavioral design pattern that allows making snapshots of an object's state and restoring it in future.
The Memento doesn't compromise the internal structure of the object it works with, as well as data kept inside the snapshots.
在 PHP 中使用模式
Usage examples: The actual applicability of the Memento pattern in PHP is very questionable. In most cases, you could make a copy of an object's state easier by simply using serialization.