How to modify app.config at runtime

When you try to modify the app.config at runtime, if you don’t do it right, you’ll run into a few problems: You’ll get the following exception: System.Configuration.ConfigurationErrorsException: The configuration is read only. The updated value isn’t persisted. When you re-open your program, the value you changed is still the old value. This article will show … Read more How to modify app.config at runtime