wpf可以对控件外观使用xaml重写模板，默认的外观在(Program Files)\Windows Kits\10\DesignTime\CommonConfiguration\Neutral\UAP;SDK version>\Generic，如果你安装了win10SDK的话，如果没有可以在其他sdk中类似路径寻找。
对于Slider控件，简单的重写了一下style，瞬间让滑动条变得粗壮了许多，如下图所示：
根据sdk模板对照修改是一个简单的办法。首先在xaml设计视图里面（不是代码），右键点击slider控件（其他控件也可以），选择编辑模板，就默认模板会自动填充在代码区，如果vs版本低的话可能需要按照上面的办法手动查看generic.xaml文件。
对于slider小小改动一下，就成了上面图片的外观。
<Style TargetType="Slider" x:Key="MySlider">
<Setter Property="Background" Value="White" />
<Setter Property="BorderThickness" Value="1" />
<Setter Property="Foreground" Value="HotPink" />
<Setter Property="FontFamily" Value="youyuan" />
<Setter Property="FontSize" Value="30" />
<Setter Property="ManipulationMode" Value="None" />
<Setter Property="UseSystemFocusVisuals" Value="True" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Slider">
<Grid Margin="10">
<Grid.Resources>
<Style TargetType="Thumb" x:Key="SliderThumbStyle">
<Setter Property="BorderThickness" Value="0" />
<Setter Property="Background" Value="Plum" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Thumb">
<Border Background="Black" BorderBrush="Blue" BorderThickness="1" CornerRadius="0" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Grid.Resources>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid x:Name="SliderContainer" Background="Transparent" Grid.Row="1" Control.IsTemplateFocusTarget="True">
<Grid x:Name="HorizontalTemplate" MinHeight="44">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="18" />
<RowDefinition Height="Auto" />
<RowDefinition Height="18" />
</Grid.RowDefinitions>
<Rectangle x:Name="HorizontalTrackRect" Fill="{TemplateBinding Background}" Height="12" Grid.Row="1" Grid.ColumnSpan="3" />
<Rectangle x:Name="HorizontalDecreaseRect" Fill="{TemplateBinding Foreground}" Grid.Row="1" />
<TickBar x:Name="TopTickBar" Visibility="Collapsed" Fill="{ThemeResource SystemControlForegroundBaseMediumLowBrush}" Height="{ThemeResource SliderOutsideTickBarThemeHeight}" VerticalAlignment="Bottom" Margin="0,0,0,4" Grid.ColumnSpan="3" />
<TickBar x:Name="HorizontalInlineTickBar" Visibility="Collapsed" Fill="{ThemeResource SystemControlBackgroundAltHighBrush}" Height="{ThemeResource SliderTrackThemeHeight}" Grid.Row="1" Grid.ColumnSpan="3" />
<TickBar x:Name="BottomTickBar" Visibility="Collapsed" Fill="{ThemeResource SystemControlForegroundBaseMediumLowBrush}" Height="{ThemeResource SliderOutsideTickBarThemeHeight}" VerticalAlignment="Top" Margin="0,4,0,0" Grid.Row="2" Grid.ColumnSpan="3" />
<Thumb x:Name="HorizontalThumb" Background="Black" Style="{StaticResource SliderThumbStyle}" DataContext="{TemplateBinding Value}" Height="40" Width="15" Grid.Row="0" Grid.RowSpan="3" Grid.Column="1" AutomationProperties.AccessibilityView="Raw" />
</Grid>
<Grid x:Name="VerticalTemplate" MinWidth="44" Visibility="Collapsed">
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="18" />
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="18" />
</Grid.ColumnDefinitions>
<Rectangle x:Name="VerticalTrackRect" Fill="{TemplateBinding Background}" Width="{ThemeResource SliderTrackThemeHeight}" Grid.Column="1" Grid.RowSpan="3" />
<Rectangle x:Name="VerticalDecreaseRect" Fill="{TemplateBinding Foreground}" Grid.Column="1" Grid.Row="2" />
<TickBar x:Name="LeftTickBar" Visibility="Collapsed" Fill="{ThemeResource SystemControlForegroundBaseMediumLowBrush}" Width="{ThemeResource SliderOutsideTickBarThemeHeight}" HorizontalAlignment="Right" Margin="0,0,4,0" Grid.RowSpan="3" />
<TickBar x:Name="VerticalInlineTickBar" Visibility="Collapsed" Fill="{ThemeResource SystemControlBackgroundAltHighBrush}" Width="{ThemeResource SliderTrackThemeHeight}" Grid.Column="1" Grid.RowSpan="3" />
<TickBar x:Name="RightTickBar" Visibility="Collapsed" Fill="{ThemeResource SystemControlForegroundBaseMediumLowBrush}" Width="{ThemeResource SliderOutsideTickBarThemeHeight}" HorizontalAlignment="Left" Margin="4,0,0,0" Grid.Column="2" Grid.RowSpan="3" />
<Thumb x:Name="VerticalThumb" Background="{ThemeResource SystemControlForegroundAccentBrush}" Style="{StaticResource SliderThumbStyle}" DataContext="{TemplateBinding Value}" Width="24" Height="8" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="3" AutomationProperties.AccessibilityView="Raw" />
</Grid>
</Grid>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
备注：slider的其他引用资源
| Resource key | Description |
|---|---|
| SliderContainerBackground | Background color at rest |
| SliderContainerBackgroundPointerOver | Background color on hover |
| SliderContainerBackgroundPressed | Background color when pressed |
| SliderContainerBackgroundDisabled | Background color when disabled |
| SliderThumbBackground | Background color of the thumb at rest |
| SliderThumbBackgroundPointerOver | Background color of the thumb on hover |
| SliderThumbBackgroundPressed | Background color of the thumb when pressed |
| SliderThumbBackgroundDisabled | Background color of the thumb when disabled |
| SliderTrackFill | Color of unfilled portion of track |
| SliderTrackFillPointerOver | Color of unfilled portion of track on hover |
| SliderTrackFillPressed | Color of unfilled portion of track when pressed |
| SliderTrackFillDisabled | Color of unfilled portion of track when disabled |
| SliderTrackValueFill | Color of filled portion of track |
| SliderTrackValueFillPointerOver | Color of filled portion of track on hover |
| SliderTrackValueFillPressed | Color of filled portion of track when pressed |
| SliderTrackValueFillDisabled | Color of filled portion of track when disabled |
| SliderHeaderForeground | Foreground color of the label |
| SliderHeaderForegroundDisabled | Foreground color of the label when disabled |
| SliderTickBarFill | Color of the tick marks |
| SliderTickBarFillDisabled | Color of the tick marks when disabled |
| SliderInlineTickBarFill | Color of inline tick marks |
<SolidColorBrush x:Key="SliderTrackValueFill" Color="#FFC8D6C9" />
<SolidColorBrush x:Key="SliderTrackValueFillPressed" Color="Gainsboro" />
<SolidColorBrush x:Key="SliderTrackValueFillDisabled" Color="#FFDADAE8" />
<SolidColorBrush x:Key="SliderTrackValueFillPointerOver" Color="#FFC2C2DA" />
<Style x:Key="SliderStyle1" TargetType="Slider">
<Setter Property="Background" Value="{ThemeResource SliderTrackFill}" />
<Setter Property="BorderThickness" Value="{ThemeResource SliderBorderThemeThickness}" />
<Setter Property="Foreground" Value="{ThemeResource SliderTrackValueFill}" />
<Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}" />
<Setter Property="FontSize" Value="{ThemeResource ControlContentThemeFontSize}" />
<Setter Property="ManipulationMode" Value="None" />
<Setter Property="UseSystemFocusVisuals" Value="{StaticResource UseSystemFocusVisuals}" />
<Setter Property="FocusVisualMargin" Value="-7,0,-7,0" />
<Setter Property="IsFocusEngagementEnabled" Value="True" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Slider">
<Grid Margin="{TemplateBinding Padding}">
<Grid.Resources>
<Style x:Key="SliderThumbStyle" TargetType="Thumb">
<Setter Property="BorderThickness" Value="0" />
<Setter Property="Background" Value="{ThemeResource SliderThumbBackground}" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Thumb">
<Border Background="OrangeRed" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" CornerRadius="20" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Grid.Resources>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<ContentPresenter x:Name="HeaderContentPresenter" Grid.Row="0" Margin="{ThemeResource SliderTopHeaderMargin}" x:DeferLoadStrategy="Lazy" Content="{TemplateBinding Header}" ContentTemplate="{TemplateBinding HeaderTemplate}" FontWeight="{ThemeResource SliderHeaderThemeFontWeight}" Foreground="{ThemeResource SliderHeaderForeground}" TextWrapping="Wrap" Visibility="Collapsed" />
<Grid x:Name="SliderContainer" Grid.Row="1" Background="{ThemeResource SliderContainerBackground}" Control.IsTemplateFocusTarget="True">
<Grid x:Name="HorizontalTemplate" MinHeight="{ThemeResource SliderHorizontalHeight}">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="{ThemeResource SliderPreContentMargin}" />
<RowDefinition Height="Auto" />
<RowDefinition Height="{ThemeResource SliderPostContentMargin}" />
</Grid.RowDefinitions>
<Rectangle x:Name="HorizontalTrackRect" Grid.Row="1" Grid.ColumnSpan="3" Height="{ThemeResource SliderTrackThemeHeight}" Fill="{TemplateBinding Background}" />
<Rectangle x:Name="HorizontalDecreaseRect" Grid.Row="1" Fill="{TemplateBinding Foreground}" />
<TickBar x:Name="TopTickBar" Grid.ColumnSpan="3" Height="{ThemeResource SliderOutsideTickBarThemeHeight}" Margin="0,0,0,4" VerticalAlignment="Bottom" Fill="{ThemeResource SliderTickBarFill}" Visibility="Collapsed" />
<TickBar x:Name="HorizontalInlineTickBar" Grid.Row="1" Grid.ColumnSpan="3" Height="{ThemeResource SliderTrackThemeHeight}" Fill="{ThemeResource SliderInlineTickBarFill}" Visibility="Collapsed" />
<TickBar x:Name="BottomTickBar" Grid.Row="2" Grid.ColumnSpan="3" Height="{ThemeResource SliderOutsideTickBarThemeHeight}" Margin="0,4,0,0" VerticalAlignment="Top" Fill="{ThemeResource SliderTickBarFill}" Visibility="Collapsed" />
<Thumb x:Name="HorizontalThumb" Grid.Row="0" Grid.RowSpan="3" Grid.Column="1" Width="20" Height="20" AutomationProperties.AccessibilityView="Raw" DataContext="{TemplateBinding Value}" FocusVisualMargin="-14,-6,-14,-6" Style="{StaticResource SliderThumbStyle}" />
</Grid>
<Grid x:Name="VerticalTemplate" MinWidth="{ThemeResource SliderVerticalWidth}" Visibility="Collapsed">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="{ThemeResource SliderPreContentMargin}" />
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="{ThemeResource SliderPostContentMargin}" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Rectangle x:Name="VerticalTrackRect" Grid.RowSpan="3" Grid.Column="1" Width="{ThemeResource SliderTrackThemeHeight}" Fill="{TemplateBinding Background}" />
<Rectangle x:Name="VerticalDecreaseRect" Grid.Row="2" Grid.Column="1" Fill="{TemplateBinding Foreground}" />
<TickBar x:Name="LeftTickBar" Grid.RowSpan="3" Width="{ThemeResource SliderOutsideTickBarThemeHeight}" Margin="0,0,4,0" HorizontalAlignment="Right" Fill="{ThemeResource SliderTickBarFill}" Visibility="Collapsed" />
<TickBar x:Name="VerticalInlineTickBar" Grid.RowSpan="3" Grid.Column="1" Width="{ThemeResource SliderTrackThemeHeight}" Fill="{ThemeResource SliderInlineTickBarFill}" Visibility="Collapsed" />
<TickBar x:Name="RightTickBar" Grid.RowSpan="3" Grid.Column="2" Width="{ThemeResource SliderOutsideTickBarThemeHeight}" Margin="4,0,0,0" HorizontalAlignment="Left" Fill="{ThemeResource SliderTickBarFill}" Visibility="Collapsed" />
<Thumb x:Name="VerticalThumb" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="3" Width="24" Height="8" AutomationProperties.AccessibilityView="Raw" DataContext="{TemplateBinding Value}" FocusVisualMargin="-6,-14,-6,-14" Style="{StaticResource SliderThumbStyle}" />
</Grid>
</Grid>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal" />
<VisualState x:Name="Pressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HorizontalTrackRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackFillPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="VerticalTrackRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackFillPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HorizontalThumb" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderThumbBackgroundPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="VerticalThumb" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderThumbBackgroundPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="SliderContainer" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderContainerBackgroundPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HorizontalDecreaseRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackValueFillPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="VerticalDecreaseRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackValueFillPressed}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HeaderContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderHeaderForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HorizontalDecreaseRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackValueFillDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HorizontalTrackRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackFillDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="VerticalDecreaseRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackValueFillDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="VerticalTrackRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackFillDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HorizontalThumb" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderThumbBackgroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="VerticalThumb" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderThumbBackgroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="TopTickBar" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTickBarFillDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="BottomTickBar" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTickBarFillDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="LeftTickBar" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTickBarFillDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RightTickBar" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTickBarFillDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="SliderContainer" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderContainerBackgroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="PointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HorizontalTrackRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackFillPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="VerticalTrackRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackFillPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HorizontalThumb" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderThumbBackgroundPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="VerticalThumb" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderThumbBackgroundPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="SliderContainer" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderContainerBackgroundPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HorizontalDecreaseRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackValueFillPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="VerticalDecreaseRect" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SliderTrackValueFillPointerOver}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
<VisualStateGroup x:Name="FocusEngagementStates">
<VisualState x:Name="FocusDisengaged" />
<VisualState x:Name="FocusEngagedHorizontal">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="SliderContainer" Storyboard.TargetProperty="(Control.IsTemplateFocusTarget)">
<DiscreteObjectKeyFrame KeyTime="0" Value="False" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HorizontalThumb" Storyboard.TargetProperty="(Control.IsTemplateFocusTarget)">
<DiscreteObjectKeyFrame KeyTime="0" Value="True" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="FocusEngagedVertical">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="SliderContainer" Storyboard.TargetProperty="(Control.IsTemplateFocusTarget)">
<DiscreteObjectKeyFrame KeyTime="0" Value="False" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="VerticalThumb" Storyboard.TargetProperty="(Control.IsTemplateFocusTarget)">
<DiscreteObjectKeyFrame KeyTime="0" Value="True" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>