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PODefault conversion fails when DatePicker.SelectedDate set to null
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  1. PODefault conversion fails when DatePicker.SelectedDate set to null
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    copied!<p>I'm binding a property of <code>DateTime?</code> to a DatePicker's SelectedDate and DisplayDate properties. It's behaving exactly as I'd like, but I notice this error in the VS Output window. </p> <pre><code>System.Windows.Data Error: 23 : Cannot convert '&lt;null&gt;' from type '&lt;null&gt;' to type 'System.DateTime' for 'en-US' culture with default conversions; consider using Converter property of Binding. NotSupportedException:'System.NotSupportedException: 'DateTimeValueSerializer' ValueSerializer cannot convert from '(null)'. at System.Windows.Markup.DateTimeValueSerializer.ConvertFromString(String value, IValueSerializerContext context) at System.Xaml.Replacements.DateTimeConverter2.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value) at MS.Internal.Data.DefaultValueConverter.ConvertHelper(Object o, Type destinationType, DependencyObject targetElement, CultureInfo culture, Boolean isForward)' </code></pre> <p>I've been able to remove the error by converting <code>null</code> to <code>DateTime.Now</code> or to some other default date but that isn't the behavior I want - my DatePicker should show "Select a date" when the value is null, just like it does now.</p> <p>Should I make any special effort to eliminate this error?</p> <p>If so, how might I approach this?</p> <h2>Additional</h2> <p>The <code>DatePicker</code> in question is part of the <code>ControlTemplate</code> of a <code>ContentControl</code>. Here is a slightly distilled version of what I'm doing: </p> <pre><code>&lt;ContentControl Content="{Binding Path=MyDateProperty, Mode=TwoWay}"&gt; &lt;ContentControl.Template&gt; &lt;ControlTemplate TargetType="ContentControl"&gt; &lt;DatePicker DisplayDate="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=Content}" SelectedDate="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=Content}"/&gt; &lt;/ControlTemplate&gt; &lt;/ContentControl.Template&gt; &lt;/ContentControl&gt; </code></pre> <p>In actual fact the template is selected and the bindings set in code, but this generates the errors I'm seeing.</p>
 

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