c# - Entity Framework ConnectionString won't update after changing App.Config in runtime

Entity Framework caches connection string, there isn't a method to force a refresh.

From this article: connection string given in DbContext constructor isn't cached then you can use this as workaround:

public class MyContext : DbContext {
    public MyContext()
        : base(ConfigurationManager.ConnectionStrings["MyConnection"].ConnectionString)
    {
    }
}