要使树形层级结构的详细信息与头部标题对齐，可以使用Grid布局将每一列的信息与头部标题对齐。为此，我们需要确保TreeViewItem的每一列宽度与头部标题的列宽度一致。

修改后的WPF布局示例

<Grid Margin="0,8,0,8">
    <!-- 页面整体分两列 -->
    <Grid.ColumnDefinitions>
        <ColumnDefinition />
        <ColumnDefinition Width="86" />
    </Grid.ColumnDefinitions>
    <!-- 第一列 程序管理主页面 -->
    <Grid Grid.Column="0">
        <Grid.RowDefinitions>
            <RowDefinition Height="48" />
            <RowDefinition Height="274" />
            <RowDefinition Height="2" />
            <RowDefinition Height="274" />
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>

        <!-- 顶栏 -->
        <Border Grid.Row="0" Margin="8,0,8,0" Background="#FFFFFF" BorderBrush="#D1D6E0" BorderThickness="1,1,1,0" CornerRadius="4 4 0 0">
            <Grid Margin="4,4,4,4">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="2*" />
                    <ColumnDefinition Width="8*" />
                    <ColumnDefinition Width="86" />
                    <ColumnDefinition Width="50" />
                    <ColumnDefinition Width="60" />
                    <ColumnDefinition Width="80" />
                    <ColumnDefinition Width="80" />
                    <ColumnDefinition Width="60" />
                    <ColumnDefinition Width="40" />
                </Grid.ColumnDefinitions>
                <TextBlock Grid.Column="0" VerticalAlignment="Center" FontSize="16" Foreground="#385278" Text="文件夹" TextAlignment="Center" />
                <TextBlock Grid.Column="1" VerticalAlignment="Center" FontSize="16" Foreground="#385278" Text="EXT." TextAlignment="Center" />
                <TextBlock Grid.Column="2" VerticalAlignment="Center" FontSize="16" Foreground="#385278" Text="大小" TextAlignment="Center" />
                <TextBlock Grid.Column="3" VerticalAlignment="Center" FontSize="16" Foreground="#385278" Text="文件" TextAlignment="Center" />
                <TextBlock Grid.Column="4" VerticalAlignment="Center" FontSize="16" Foreground="#385278" Text="备注" TextAlignment="Center" />
                <TextBlock Grid.Column="5" VerticalAlignment="Center" FontSize="16" Foreground="#385278" Text="修改" TextAlignment="Center" />
                <TextBlock Grid.Column="6" VerticalAlignment="Center" FontSize="16" Foreground="#385278" Text="存储" TextAlignment="Center" />
                <TextBlock Grid.Column="7" VerticalAlignment="Center" FontSize="16" Foreground="#385278" Text="属性" TextAlignment="Center" />
            </Grid>
        </Border>

        <!-- PC区树状目录结构 -->
        <Border Grid.Row="1" Margin="8,0,8,0" Background="#FFFFFF" BorderBrush="#33375278" BorderThickness="1,1,1,0">
            <Border.Effect>
                <DropShadowEffect BlurRadius="10" Direction="315" Opacity="0.2" ShadowDepth="2" Color="#377484" />
            </Border.Effect>
            <TreeView x:Name="PCtree" Height="273" VerticalAlignment="Bottom" ItemContainerStyle="{StaticResource TreeViewItemStyle}" ItemsSource="{Binding PCModels}">
                <TreeView.Resources>
                    <local:FileFolderTemplateSelector x:Key="FileFolderTemplateSelector" DirectoryDataTemplate="{StaticResource DirectoryDataTemplate}" FileDataTemplate="{StaticResource FileDataTemplate}" />
                </TreeView.Resources>
                <TreeView.ItemTemplateSelector>
                    <StaticResource ResourceKey="FileFolderTemplateSelector" />
                </TreeView.ItemTemplateSelector>
            </TreeView>
        </Border>

        <!-- 文件详细信息模板 -->
        <HierarchicalDataTemplate x:Key="FileDataTemplate" DataType="{x:Type local:PCModel}" ItemsSource="{Binding Children}">
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="2*" />
                    <ColumnDefinition Width="8*" />
                    <ColumnDefinition Width="86" />
                    <ColumnDefinition Width="50" />
                    <ColumnDefinition Width="60" />
                    <ColumnDefinition Width="80" />
                    <ColumnDefinition Width="80" />
                    <ColumnDefinition Width="60" />
                    <ColumnDefinition Width="40" />
                </Grid.ColumnDefinitions>
                <StackPanel Grid.Column="0" Margin="2" Orientation="Horizontal">
                    <Image Width="16" Height="16" Margin="10,6" Source="{DynamicResource FileDocumentIcon}" Stretch="Uniform" />
                    <TextBlock Margin="0,1,0,0" FontSize="14" Foreground="#375278" Text="{Binding Name}" />
                </StackPanel>
                <TextBlock Grid.Column="1" Margin="20,0,0,0" FontSize="14" Foreground="#375278" Text="{Binding FileDetail.PCFileExt}" />
                <TextBlock Grid.Column="2" Margin="20,0,0,0" FontSize="14" Foreground="#375278" Text="{Binding FileDetail.PCFileSize}" />
                <TextBlock Grid.Column="3" Margin="20,0,0,0" FontSize="14" Foreground="#375278" Text="{Binding FileDetail.PCNCFileName}" />
                <TextBlock Grid.Column="4" Margin="20,0,0,0" FontSize="14" Foreground="#375278" Text="{Binding FileDetail.PCFileComment}" />
                <TextBlock Grid.Column="5" Margin="20,0,0,0" FontSize="14" Foreground="#375278" Text="{Binding FileDetail.PCFileModify}" />
                <TextBlock Grid.Column="6" Margin="20,0,0,0" FontSize="14" Foreground="#375278" Text="{Binding FileDetail.PCFileStorage}" />
                <TextBlock Grid.Column="7" Margin="20,0,0,0" FontSize="14" Foreground="#375278" Text="{Binding FileDetail.PCFileAttributes}" />
            </Grid>
        </HierarchicalDataTemplate>
    </Grid>
</Grid>

关键修改点

1. 统一列定义：在顶栏和文件详细信息的模板中使用相同的Grid.ColumnDefinitions，确保每一列的宽度一致。
2. 调整StackPanel：将顶栏的TextBlock控件放置在Grid的列中，而不是使用StackPanel，这样每一列的信息能够对齐。

这样，通过确保顶栏和树状目录项使用相同的列定义，信息能够正确对齐。