Avalonia/samples/ControlCatalog/Pages/DateTimePickerPage.xaml

<UserControl xmlns="https://github.com/avaloniaui"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             xmlns:sys="using:System"
             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
             x:Class="ControlCatalog.Pages.DateTimePickerPage">
  <StackPanel Orientation="Vertical" Spacing="4" HorizontalAlignment="Stretch">
    <TextBlock Name="DatePickerDesc" Classes="h2" TextWrapping="Wrap"/>
    <TextBlock Name="TimePickerDesc" Classes="h2" TextWrapping="Wrap"/>

    <StackPanel Orientation="Vertical"
                Margin="16"
                HorizontalAlignment="Stretch"
                Spacing="16">
      <TextBlock FontSize="18">A simple DatePicker</TextBlock>
      <StackPanel Orientation="Vertical">
        <Border BorderBrush="{DynamicResource CatalogBaseLowColor}"
                BorderThickness="1" Padding="15">
          <DatePicker />
        </Border>
        <Panel Background="{DynamicResource CatalogBaseLowColor}">
          <TextBlock Padding="15">
            <TextBlock.Text>
              <x:String>
                &lt;DatePicker/&gt;
              </x:String>
            </TextBlock.Text>
          </TextBlock>
        </Panel>
      </StackPanel>
      
      
      <Border BorderBrush="{DynamicResource CatalogBaseLowColor}"
              BorderThickness="1" Padding="15">
        <DatePicker >
          <DataValidationErrors.Error>
            <sys:Exception /> 
          </DataValidationErrors.Error>
        </DatePicker>
      </Border>
      
      <TextBlock FontSize="18">A DatePicker with day formatted and year hidden.</TextBlock>
      <StackPanel Orientation="Vertical">
        <Border BorderBrush="{DynamicResource CatalogBaseLowColor}"
                BorderThickness="1" Padding="15">
          <DatePicker x:Name="Control2" DayFormat="d (ddd)"
                             YearVisible="False" />
        </Border>
        <Panel Background="{DynamicResource CatalogBaseLowColor}">
          <TextBlock Padding="15">
            <TextBlock.Text>
              <x:String>
                &lt;DatePicker DayFormat="d (ddd)" YearVisible="False" /&gt;
              </x:String>
            </TextBlock.Text>
          </TextBlock>
        </Panel>
      </StackPanel>

      <Border Background="{DynamicResource CatalogBaseLowColor}" BorderThickness="1" Margin="15" />

      <TextBlock FontSize="18">A simple TimePicker.</TextBlock>
      <StackPanel Orientation="Vertical">
        <Border BorderBrush="{DynamicResource CatalogBaseLowColor}"
                BorderThickness="1" Padding="15">
          <TimePicker />
        </Border>
        <Panel Background="{DynamicResource CatalogBaseLowColor}">
          <TextBlock Padding="15">
            <TextBlock.Text>
              <x:String>
                &lt;TimePicker /&gt;
              </x:String>
            </TextBlock.Text>
          </TextBlock>
        </Panel>
      </StackPanel>
      
      <Border BorderBrush="{DynamicResource CatalogBaseLowColor}"
              BorderThickness="1" Padding="15">
        <TimePicker>
          <DataValidationErrors.Error>
            <sys:Exception /> 
          </DataValidationErrors.Error>
        </TimePicker>
      </Border>

      <TextBlock FontSize="18">A TimePicker with minute increments specified.</TextBlock>
      <StackPanel Orientation="Vertical">
        <Border BorderBrush="{DynamicResource CatalogBaseLowColor}"
                BorderThickness="1" Padding="15">
          <TimePicker MinuteIncrement="15" />
        </Border>
        <Panel Background="{DynamicResource CatalogBaseLowColor}">
          <TextBlock Padding="15">
            <TextBlock.Text>
              <x:String>
                &lt;TimePicker MinuteIncrement="15" /&gt;
              </x:String>
            </TextBlock.Text>
          </TextBlock>
        </Panel>
      </StackPanel>

      <TextBlock FontSize="18">A TimePicker using a 12-hour clock.</TextBlock>
      <StackPanel Orientation="Vertical">
        <Border BorderBrush="{DynamicResource CatalogBaseLowColor}"
                BorderThickness="1" Padding="15">
          <TimePicker ClockIdentifier="12HourClock"/>
        </Border>
        <Panel Background="{DynamicResource CatalogBaseLowColor}">
          <TextBlock Padding="15">
            <TextBlock.Text>
              <x:String>
                &lt;TimePicker ClockIdentifier="12HourClock" /&gt;
              </x:String>
            </TextBlock.Text>
          </TextBlock>
        </Panel>
      </StackPanel>

      <TextBlock FontSize="18">A TimePicker using a 24-hour clock.</TextBlock>
      <StackPanel Orientation="Vertical">
        <Border BorderBrush="{DynamicResource CatalogBaseLowColor}"
                BorderThickness="1" Padding="15">
          <TimePicker ClockIdentifier="24HourClock" />
        </Border>
        <Panel Background="{DynamicResource CatalogBaseLowColor}">
          <TextBlock Padding="15">
            <TextBlock.Text>
              <x:String>
                &lt;TimePicker ClockIdentifier="24HourClock" /&gt;
              </x:String>
            </TextBlock.Text>
          </TextBlock>
        </Panel>
      </StackPanel>
      
    </StackPanel>
  </StackPanel>
</UserControl>