I am making a simple editor where via a UI, the user can change parameters of my 3D display. The UI is basically a mirror of some backend data. So when a UI value changes (I listen for the event), I update the backend variable and repaint. I come across one issue. In my backend class, I initialize the data to default values. Then in the UI Form constructor, I want to initialize the UI controls based on the default values. So something like this:

public MainForm()
        {
            InitializeComponent();

            numIntensityRed.Value   = Convert.ToDecimal(d3dControl.IntensityRed.X);
            numIntensityGreen.Value = Convert.ToDecimal(d3dControl.IntensityGreen.Y);
            numIntensityBlue.Value  = Convert.ToDecimal(d3dControl.IntensityBlue.Z);
        }

where "num" are numeric up/down controls. The problem is that this assignment raises the ValueChanged event of the numeric up/down controls, which then goes and sets the d3DControl properties again. This isn't really a problem, although it seems strange because the d3dControl properties don't need to be set here. It seems like this is a common issue with UI frontends for backends. What is the proper pattern to do this? Should I hook up the event handlers after I initalize the control values?

Yeah, it doesn't hurt anything, but it seems like a waste of effort. The backend is already initialized, but then gets set again to the same value.