Question

I have a DatePicker bound to a DataTime within an object, and at run time, instead of the string “Select a Date” in DatePicker, “1/1/0001” is shown, making it hard to use the actual calendar. I did not have a problem when I was binding DatePicker with a string, but changing it to a DateTime did this. Please let me know how this works. This is what I have so far:

In XAML I have:

<DatePicker Grid.Column="4" Grid.Row="9" Name="dueDateBox" VerticalAlignment="Center">
    <DatePicker.SelectedDate>
        <Binding Path="DueDate" UpdateSourceTrigger="PropertyChanged" Mode="TwoWay">
            <Binding.ValidationRules>
                <my:DateRangeRule/>
            </Binding.ValidationRules>
        </Binding>
    </DatePicker.SelectedDate>
</DatePicker>

In the C# I have:

public DateTime DueDate
{
    get { return dueDate; }
    set
    {
        if (DueDate != null) || !DueDate.Equals(value))
        {
            dueDate = value;
            OnPropertyChanged("DueDate");
        }
    }
}

I also have a dependency property set, not sure if this is playing a part:

public static readonly DependencyProperty DueDateProperty =
        DependencyProperty.Register("DueDate", typeof(DateTime),
        typeof(UpdateJobDialog), new PropertyMetadata(DateTime.Now));

Answer 1

Would probably help to use DateTime? instead of DateTime, since DateTime is not nullable, you are setting to the default value of 1/1/0001, rather than null which would result in the please select a date message you are used to.

public DateTime? DueDate
{
    //Need to change the type of the private variable as well
    get { return dueDate; }
    set
    {
        if (DueDate != null) || !DueDate.Equals(value))
        {
            dueDate = value;
            OnPropertyChanged("DueDate");
        }
    }
}