Semi.Avalonia/src/Semi.Avalonia/Controls/TabControl.axaml

<ResourceDictionary
    xmlns="https://github.com/avaloniaui"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <Design.PreviewWith>
        <StackPanel Width="400" Height="400" Margin="20">
            <TabControl
                Theme="{DynamicResource LineTabControl}"
                TabStripPlacement="Top">
                <TabItem Header="文档">
                    <TextBlock Text="Content1" />
                </TabItem>
                <TabItem Header="快速起步" IsEnabled="False">
                    <TextBlock Text="Content2" />
                </TabItem>
                <TabItem Header="帮助" IsSelected="True">
                    <TextBlock Text="Content3" />
                </TabItem>
            </TabControl>
        </StackPanel>
    </Design.PreviewWith>

    <ControlTheme x:Key="BaseTabControl" TargetType="TabControl">
        <Setter Property="Template">
            <ControlTemplate TargetType="TabControl">
                <Border
                    HorizontalAlignment="{TemplateBinding HorizontalAlignment}"
                    VerticalAlignment="{TemplateBinding VerticalAlignment}"
                    Background="{TemplateBinding Background}"
                    BorderBrush="{TemplateBinding BorderBrush}"
                    BorderThickness="{TemplateBinding BorderThickness}"
                    CornerRadius="{TemplateBinding CornerRadius}">
                    <DockPanel>
                        <Panel DockPanel.Dock="{TemplateBinding TabStripPlacement}">
                            <ItemsPresenter
                                Name="PART_ItemsPresenter"
                                ItemsPanel="{TemplateBinding ItemsPanel}" />
                            <Border Name="PART_BorderSeparator" />
                        </Panel>
                        <ContentPresenter
                            Name="PART_SelectedContentHost"
                            Margin="{TemplateBinding Padding}"
                            HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
                            VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
                            Content="{TemplateBinding SelectedContent}"
                            ContentTemplate="{TemplateBinding SelectedContentTemplate}" />
                    </DockPanel>
                </Border>
            </ControlTemplate>
        </Setter>

        <Style Selector="^[TabStripPlacement=Left], ^[TabStripPlacement=Right]">
            <Setter Property="TabControl.ItemsPanel">
                <ItemsPanelTemplate>
                    <WrapPanel Orientation="Vertical" />
                </ItemsPanelTemplate>
            </Setter>
        </Style>

        <Style Selector="^ /template/ Border#PART_BorderSeparator">
            <Setter Property="Background" Value="{DynamicResource TabControlSeparatorBorderBrush}" />
        </Style>

        <Style Selector="^[TabStripPlacement=Top] /template/ Border#PART_BorderSeparator">
            <Setter Property="Height" Value="1" />
            <Setter Property="VerticalAlignment" Value="Bottom" />
        </Style>
        <Style Selector="^[TabStripPlacement=Bottom] /template/ Border#PART_BorderSeparator">
            <Setter Property="Height" Value="1" />
            <Setter Property="VerticalAlignment" Value="Top" />
        </Style>
        <Style Selector="^[TabStripPlacement=Left] /template/ Border#PART_BorderSeparator">
            <Setter Property="Width" Value="1" />
            <Setter Property="HorizontalAlignment" Value="Right" />
        </Style>
        <Style Selector="^[TabStripPlacement=Right] /template/ Border#PART_BorderSeparator">
            <Setter Property="Width" Value="1" />
            <Setter Property="HorizontalAlignment" Value="Left" />
        </Style>
    </ControlTheme>

    <ControlTheme
        x:Key="{x:Type TabControl}"
        BasedOn="{StaticResource BaseTabControl}"
        TargetType="TabControl">
        <Style Selector="^[TabStripPlacement=Left] /template/ Border#PART_BorderSeparator">
            <Setter Property="HorizontalAlignment" Value="Left" />
        </Style>
        <Style Selector="^[TabStripPlacement=Right] /template/ Border#PART_BorderSeparator">
            <Setter Property="HorizontalAlignment" Value="Right" />
        </Style>

        <Style Selector="^.ReverseSeparator">
            <Style Selector="^[TabStripPlacement=Left] /template/ Border#PART_BorderSeparator">
                <Setter Property="HorizontalAlignment" Value="Right" />
            </Style>
            <Style Selector="^[TabStripPlacement=Left]">
                <Setter Property="ItemContainerTheme">
                    <ControlTheme
                        BasedOn="{StaticResource {x:Type TabItem}}"
                        TargetType="TabItem">
                        <Style Selector="^[TabStripPlacement=Left]">
                            <Setter Property="BorderThickness" Value="0 0 2 0" />
                        </Style>
                    </ControlTheme>
                </Setter>
            </Style>
            <Style Selector="^[TabStripPlacement=Right] /template/ Border#PART_BorderSeparator">
                <Setter Property="HorizontalAlignment" Value="Left" />
            </Style>
            <Style Selector="^[TabStripPlacement=Right]">
                <Setter Property="ItemContainerTheme">
                    <ControlTheme
                        BasedOn="{StaticResource {x:Type TabItem}}"
                        TargetType="TabItem">
                        <Style Selector="^[TabStripPlacement=Right]">
                            <Setter Property="BorderThickness" Value="2 0 0 0" />
                        </Style>
                    </ControlTheme>
                </Setter>
            </Style>
        </Style>
    </ControlTheme>

    <ControlTheme
        x:Key="LineTabControl"
        BasedOn="{StaticResource BaseTabControl}"
        TargetType="TabControl">
        <Setter Property="ItemContainerTheme" Value="{StaticResource LineTabItem}" />
    </ControlTheme>

    <ControlTheme
        x:Key="CardTabControl"
        BasedOn="{StaticResource BaseTabControl}"
        TargetType="TabControl">
        <Setter Property="ItemContainerTheme" Value="{StaticResource CardTabItem}" />
        <Setter Property="Template">
            <ControlTemplate TargetType="TabControl">
                <Border
                    HorizontalAlignment="{TemplateBinding HorizontalAlignment}"
                    VerticalAlignment="{TemplateBinding VerticalAlignment}"
                    Background="{TemplateBinding Background}"
                    BorderBrush="{TemplateBinding BorderBrush}"
                    BorderThickness="{TemplateBinding BorderThickness}"
                    CornerRadius="{TemplateBinding CornerRadius}">
                    <DockPanel>
                        <Panel DockPanel.Dock="{TemplateBinding TabStripPlacement}">
                            <Border Name="PART_BorderSeparator" />
                            <ItemsPresenter
                                Name="PART_ItemsPresenter"
                                ItemsPanel="{TemplateBinding ItemsPanel}" />
                        </Panel>
                        <ContentPresenter
                            Name="PART_SelectedContentHost"
                            Margin="{TemplateBinding Padding}"
                            HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
                            VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
                            Content="{TemplateBinding SelectedContent}"
                            ContentTemplate="{TemplateBinding SelectedContentTemplate}" />
                    </DockPanel>
                </Border>
            </ControlTemplate>
        </Setter>
    </ControlTheme>

    <ControlTheme
        x:Key="ButtonTabControl"
        BasedOn="{StaticResource BaseTabControl}"
        TargetType="TabControl">
        <Setter Property="ItemContainerTheme" Value="{StaticResource ButtonTabItem}" />
        <Style Selector="^ /template/ Border#PART_BorderSeparator">
            <Setter Property="IsVisible" Value="False" />
        </Style>
    </ControlTheme>

    <!-- ScrollTabControl -->
    <ControlTheme x:Key="BaseScrollTabControl" TargetType="TabControl">
        <Setter Property="ItemsPanel">
            <ItemsPanelTemplate>
                <VirtualizingStackPanel Orientation="Horizontal" />
            </ItemsPanelTemplate>
        </Setter>
        <Setter Property="Template">
            <ControlTemplate TargetType="TabControl">
                <Border
                    HorizontalAlignment="{TemplateBinding HorizontalAlignment}"
                    VerticalAlignment="{TemplateBinding VerticalAlignment}"
                    Background="{TemplateBinding Background}"
                    BorderBrush="{TemplateBinding BorderBrush}"
                    BorderThickness="{TemplateBinding BorderThickness}"
                    CornerRadius="{TemplateBinding CornerRadius}">
                    <DockPanel>
                        <Panel DockPanel.Dock="{TemplateBinding TabStripPlacement}">
                            <ScrollViewer
                                Name="PART_ScrollViewer"
                                HorizontalScrollBarVisibility="{TemplateBinding ScrollViewer.HorizontalScrollBarVisibility}"
                                VerticalScrollBarVisibility="{TemplateBinding ScrollViewer.VerticalScrollBarVisibility}">
                                <ItemsPresenter
                                    Name="PART_ItemsPresenter"
                                    ItemsPanel="{TemplateBinding ItemsPanel}" />
                            </ScrollViewer>
                            <Border Name="PART_BorderSeparator" />
                        </Panel>
                        <ContentPresenter
                            Name="PART_SelectedContentHost"
                            Margin="{TemplateBinding Padding}"
                            HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
                            VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
                            Content="{TemplateBinding SelectedContent}"
                            ContentTemplate="{TemplateBinding SelectedContentTemplate}" />
                    </DockPanel>
                </Border>
            </ControlTemplate>
        </Setter>

        <Style Selector="^ /template/ Border#PART_BorderSeparator">
            <Setter Property="Background" Value="{DynamicResource TabControlSeparatorBorderBrush}" />
        </Style>

        <Style Selector="^[TabStripPlacement=Left], ^[TabStripPlacement=Right]">
            <Setter Property="TabControl.ItemsPanel">
                <ItemsPanelTemplate>
                    <VirtualizingStackPanel />
                </ItemsPanelTemplate>
            </Setter>
        </Style>

        <Style Selector="^[TabStripPlacement=Top] /template/ Border#PART_BorderSeparator">
            <Setter Property="Height" Value="1" />
            <Setter Property="VerticalAlignment" Value="Bottom" />
        </Style>
        <Style Selector="^[TabStripPlacement=Bottom] /template/ Border#PART_BorderSeparator">
            <Setter Property="Height" Value="1" />
            <Setter Property="VerticalAlignment" Value="Top" />
        </Style>
        <Style Selector="^[TabStripPlacement=Left] /template/ Border#PART_BorderSeparator">
            <Setter Property="Width" Value="1" />
            <Setter Property="HorizontalAlignment" Value="Right" />
        </Style>
        <Style Selector="^[TabStripPlacement=Right] /template/ Border#PART_BorderSeparator">
            <Setter Property="Width" Value="1" />
            <Setter Property="HorizontalAlignment" Value="Left" />
        </Style>

        <Style Selector="^[TabStripPlacement=Top]">
            <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto" />
            <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Disabled" />
        </Style>
        <Style Selector="^[TabStripPlacement=Bottom]">
            <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto" />
            <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Disabled" />
        </Style>
        <Style Selector="^[TabStripPlacement=Left]">
            <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Disabled" />
            <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto" />
        </Style>
        <Style Selector="^[TabStripPlacement=Right]">
            <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Disabled" />
            <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto" />
        </Style>
    </ControlTheme>

    <ControlTheme
        x:Key="ScrollTabControl"
        BasedOn="{StaticResource BaseScrollTabControl}"
        TargetType="TabControl">
        <Style Selector="^[TabStripPlacement=Left] /template/ Border#PART_BorderSeparator">
            <Setter Property="HorizontalAlignment" Value="Left" />
        </Style>
        <Style Selector="^[TabStripPlacement=Right] /template/ Border#PART_BorderSeparator">
            <Setter Property="HorizontalAlignment" Value="Right" />
        </Style>

        <Style Selector="^.ReverseSeparator">
            <Style Selector="^[TabStripPlacement=Left] /template/ Border#PART_BorderSeparator">
                <Setter Property="HorizontalAlignment" Value="Right" />
            </Style>
            <Style Selector="^[TabStripPlacement=Left]">
                <Setter Property="ItemContainerTheme">
                    <ControlTheme
                        BasedOn="{StaticResource {x:Type TabItem}}"
                        TargetType="TabItem">
                        <Style Selector="^[TabStripPlacement=Left]">
                            <Setter Property="BorderThickness" Value="0 0 2 0" />
                        </Style>
                    </ControlTheme>
                </Setter>
            </Style>
            <Style Selector="^[TabStripPlacement=Right] /template/ Border#PART_BorderSeparator">
                <Setter Property="HorizontalAlignment" Value="Left" />
            </Style>
            <Style Selector="^[TabStripPlacement=Right]">
                <Setter Property="ItemContainerTheme">
                    <ControlTheme
                        BasedOn="{StaticResource {x:Type TabItem}}"
                        TargetType="TabItem">
                        <Style Selector="^[TabStripPlacement=Right]">
                            <Setter Property="BorderThickness" Value="2 0 0 0" />
                        </Style>
                    </ControlTheme>
                </Setter>
            </Style>
        </Style>
    </ControlTheme>

    <ControlTheme
        x:Key="ScrollLineTabControl"
        BasedOn="{StaticResource BaseScrollTabControl}"
        TargetType="TabControl">
        <Setter Property="ItemContainerTheme" Value="{StaticResource LineTabItem}" />
    </ControlTheme>

    <ControlTheme
        x:Key="ScrollCardTabControl"
        BasedOn="{StaticResource BaseScrollTabControl}"
        TargetType="TabControl">
        <Setter Property="ItemContainerTheme" Value="{StaticResource CardTabItem}" />
        <Setter Property="Template">
            <ControlTemplate TargetType="TabControl">
                <Border
                    HorizontalAlignment="{TemplateBinding HorizontalAlignment}"
                    VerticalAlignment="{TemplateBinding VerticalAlignment}"
                    Background="{TemplateBinding Background}"
                    BorderBrush="{TemplateBinding BorderBrush}"
                    BorderThickness="{TemplateBinding BorderThickness}"
                    CornerRadius="{TemplateBinding CornerRadius}">
                    <DockPanel>
                        <Panel DockPanel.Dock="{TemplateBinding TabStripPlacement}">
                            <Border Name="PART_BorderSeparator" />
                            <ScrollViewer
                                Name="PART_ScrollViewer"
                                HorizontalScrollBarVisibility="{TemplateBinding ScrollViewer.HorizontalScrollBarVisibility}"
                                VerticalScrollBarVisibility="{TemplateBinding ScrollViewer.VerticalScrollBarVisibility}">
                                <ItemsPresenter
                                    Name="PART_ItemsPresenter"
                                    ItemsPanel="{TemplateBinding ItemsPanel}" />
                            </ScrollViewer>
                        </Panel>
                        <ContentPresenter
                            Name="PART_SelectedContentHost"
                            Margin="{TemplateBinding Padding}"
                            HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
                            VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
                            Content="{TemplateBinding SelectedContent}"
                            ContentTemplate="{TemplateBinding SelectedContentTemplate}" />
                    </DockPanel>
                </Border>
            </ControlTemplate>
        </Setter>
    </ControlTheme>

    <ControlTheme
        x:Key="ScrollButtonTabControl"
        BasedOn="{StaticResource BaseScrollTabControl}"
        TargetType="TabControl">
        <Setter Property="ItemContainerTheme" Value="{StaticResource ButtonTabItem}" />
        <Style Selector="^ /template/ Border#PART_BorderSeparator">
            <Setter Property="IsVisible" Value="False" />
        </Style>
    </ControlTheme>
</ResourceDictionary>