fixed #648

src/Shared/HandyControl_Shared/Themes/Styles/Base/DatePickerBaseStyle.xaml

@@ -15,6 +15,7 @@
         <Setter Property="ScrollViewer.PanningMode" Value="VerticalFirst"/>
         <Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
         <Setter Property="FocusVisualStyle" Value="{x:Null}"/>
+        <Setter Property="CaretBrush" Value="{DynamicResource PrimaryTextBrush}"/>
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="DatePickerTextBox">
@@ -348,6 +349,7 @@
     </ControlTemplate>
 
     <Style x:Key="DatePickerPlusBaseStyle" BasedOn="{StaticResource DatePickerExtendBaseStyle}" TargetType="hc:DatePicker">
+        <Setter Property="CaretBrush" Value="{DynamicResource PrimaryTextBrush}"/>
         <Setter Property="Template" Value="{StaticResource DatePickerPlusTopTemplate}"/>
         <Style.Triggers>
             <Trigger Property="hc:InfoElement.TitlePlacement" Value="Left">
@@ -357,4 +359,4 @@
         </Style.Triggers>
     </Style>
 
-</ResourceDictionary>
+</ResourceDictionary>