WPF Non-Nullable Databinding to default a cleared TextBox?

Question

I have a WPF Textbox, with the Text property bound to an int value (non nullable). When the form loads, the text box has a 0 in it. Is there any way to make this textbox default to empty?

I was setting the value to null in the code behind when the form loads, but it seems that in places, this is throwing errors that are being hidden to me, since null cannot go into the int value.. Is that bad practice? I have lots of these situations, DateTime's being set, and when the screen loads, the date is 1/1/0001, which is ugly to a user. I can default the date to todays date, but in some cases, like birthdate, that doesn't make sense.

Answer 1

You can use a value converter (see IValueConverter), or expose the int as a string from your view model:

public string Value
{
    get
    {
        if (intValue == 0)
        {
            return string.Empty;
        }

        return intValue.ToString();
    }
    set
    {
        // do conversion here
    }
}

HTH,
Kent

Answer 2

You should make your Binding one-way, using BindingMode=OneWayToSource. See MSDN for details.