C# application version management

Question

I have a C# app with its corresponding setup program. It reads startup data from the registry and stores information under the "Environment.SpecialFolder.ApplicationData"\myapp folder.

My question is: If I make various changes to the code that include new registry keys, where should I reflect this in the new version so when re-running the setup it:

• Keeps current registry keys/values
• Adds new Key/value to the registry
• Leaves "Application Data" untouched

The candidates are:

• Assembly Info
• File Version

If there are others please let me know.

Thanks

Answer 1

I think your application should be able to create the regestry keys. You don't know if the user removes them manually to reset the settings to default. The Setup should only install and register components. (But the Uninstaller should ask the User if he want to remove the settings, or keep them.)

Solution A)

To avoid version-conflicts you can remember a extra version number for configuration. As an Example: Program Version 1.0 and 2.0 are using the configuration-set 1 while Program Version 3.0 uses a configuration-set 2, because there are obsolete/new settings. Just create a sub-key in your registry tree for every configuration-set. "Application Data" can also include a subfolder with seperated configuration sets. The major advantage is, that the user can downgrade without problems. New versions can import old values from older configuration as default values.

Solution B)

Never delete (or change the type or range) settings. Just add new keys. Old program versions don't know them so they just ignoring it. This is very simple because there are no different configuration versions. But if your saving a lot of settings it can become complicated, because you cannot change the type of a setting. As an example you have to create a new key to change a setting from saving an integer to a long integer, because old versions don't understand long integers and will crash.