Question

I have the following situation. In my C# application, I have a class which i serialize using XmlSerializer. The class is pretty complex, and an object of my class gets saved on local disc as an application file, which can be opened later (classic save work and reopen work). My problems is that during the development, the class of the object which gets serialized might change. I would like to have a version system, which allows my app to realize that the saved xml it belongs to an older version but still can be opened. Old app versions can not open new xml versions as well.

For example:

class ComplexObject
{
   public string settings1;
   public string settings2;
}

I serialize object, send app in production.
Tomorrow my class became

class ComplexObject
{
   public string settings1;
   public string settings2;
   public string settings3;
}

How will my new version of app open serialized objects of old class definitions as well as new class definition with no error on loading file to object (deserialization)

Any suggestions and basic samples are welcomed!

Thanks

Answer 1

Version-tolerant serialization

In short, you either mark fields as Optional (and fill them with default values) or implement deserialization constructor which will parse values as you want them.