I'm working on a project in AutoCAD using c#, my application data is stored in complex objects (String, double, objectId, arrays, list...) and I would like to save data for later using (serialize or saved in AutoCAD drawing) and if I re-open AutoCAD and reload my project, I can find all data in my object
Sorry for my English
So You need to use XData.
Details and sample You can find here: https://www.keanw.com/2007/04/adding_xdata_to.html