Question

I have a current issue where updates to my clickonce application are messing up the connection string. This mainly happens when I make an update to a backup box and then run it on the production box for the first time (after the backup box tests). My clickonce app sees the update hosted from the backup server and pulls it down, overwriting the good IP in the process.

To the user, everything is still working but in reality they are looking at a test database.

I was reading and it appears that if I move my connection string to a “user” setting I can get it to keep the existing value. This will only work if my existing value is a non-default apparently.

So, to keep an existing user connection string I need to set a project setting default that I wont be able to use on my client machine, forcing me to modify it after the app is deployed initially?

By doing that will I pass the check that the update process does and get to keep my user configuration values?

Answer 1

I think you can solve this problem by setting the connection string in a config file within the users application data folder. When the application starts, check to see if the resource exists. If not, create it with a default value and then set change through your application. After applying the change, save it to the resource and each time the user starts his application, it should load the same resource.

To get user-specific, application data folder that is safe for click once, get the following folder path to save the configuration resource file to.

string appDataPath = 
    Path.Combine(
        Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData,
        "[Company or App Name]"));

This will give you a path that you can use to read and write data to on the end-users machine. The data in this folder will not be over-written with each deployment and the folder location is also not obfuscated like the deployment folders for your application.

If this doesn’t answer your question, please ask more in the comments. I’ll update this answer to reflect the nature of your needs.