We update our WPF app multiple times a week, this is a pain point as Customers are repeatedly asked to let the exe through their firewall.

To get around this, I will try taking most of the code (including xaml) out of the exe, so the exe never changes.

The below method seems to work, is there any reason why I should not do it this way? e.g. is it ok to have multiple Application objects?

Project: TestWpfSeperateCodeFromExe

namespace TestWpfSeperateCodeFromExe
{
    public class App
    {

        // Entry point method
        [STAThread]
        public static void Main(string[] args)
        {
                AppView.Main(args);
        }
    }
}

Project: View

namespace View
{
    public class AppView : Application
    {
        // Entry point method
        [STAThread]
        public static void Main(string[] args)
        {
            var app = new AppView();

            app.Run();
        }

        public AppView()
        {
            new MainWindow().Show();
        }
    }
}

using another application-object will most likely break many things as you have no direct control over the process - you should avoid that and use simple function/method-calls instead, these work flawlessly and thats what DLLs are for. In fact, i actually think this wont be possible in the way you imagined it.

Using DLLs like everbody does has loads of advantages, you can move 99% of your code into the DLL and make the primary entry-point (the EXE-file) absolutely static, theres no need to fiddle around with the application-object.

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