How to deserialize data if the data files may contain data from old versions of the project?

Question

.NET

How to deserialize data if the input can contain data from both the current version of the project and data from old versions of the project.

Answer 1

Store the version number in one of the data cells.
If there is no version information in the data, then make it for new versions of the project, and the absence of a version in the data will signal the old version of the product.