C# Design Pattern for save state of a file/project/work unit

Morning Everyone.

We have an application that is project based, so the user opens, create a project then there are many things that they do within that project that may or maynot need their state saving.

I have been looking around trying to find if there was an accepted pattern for this. I think the best way to describe it is to think of Visual Studio, what I am looking for is a pattern designed to recognise when one of the classes changes (putting the little star on the tab) and provides a way开发者_开发技巧 for the save routine to know what it needs to save / if anything needs to be saved.

Thanks in advance.

Looks best fit for Memento pattern.