如何显示分组项目的总和

Question

我有一个数据网格，显示扫描计数，逻辑读取等。我已经找到了如何使用转换器和显示计算单个列“扫描计数”的总和。如何为剩余的所有列做同样的事情？总和也显示在扩展器的标题中，所以它是否可以在各自列的底部对齐？

TotalSumConverter.cs

public class TotalSumConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            //First Method
            var users = value as IEnumerable<object>;
            if (users == null)
                return "";

            double sum = 0;            

            foreach (var u in users)
            {
                sum += ((AggregationTable)u).scanCount;                               
            }
            return sum.ToString();
}

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            throw new System.NotImplementedException();
        }

MainWindow.xaml

<Window.Resources>
    <local:TotalSumConverter x:Key="sumConverter" />
    <Style x:Key="GroupHeaderStyle" TargetType="{x:Type GroupItem}">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type GroupItem}">
                    <Expander x:Name="exp" IsExpanded="True"
                      Background="White"
                      Foreground="Black">
                        <Expander.Header>
                            <StackPanel Orientation="Horizontal">                                    
                                <TextBlock Grid.Column="1" Text="{Binding Path=Name}" Margin="3.5,0" />
                                <TextBlock Grid.Column="2" Text="Total:" />
                                <TextBlock Grid.Column="3" Text="{Binding Path=Items, Converter={StaticResource sumConverter}}" TextAlignment="Right" />
                            </StackPanel>
                        </Expander.Header>
                        <ItemsPresenter />
                    </Expander>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

AggregationTable.cs

    class AggregationTable
{
    string _table;
    double _scanCount;
    double _logicalreads;
    string _physicalreads;
    string _readaheadreads;
    string _loblogicalreads;
    string _lobphysicalreads;
    string _lobreadaheadreads;

    public string Table
    {
        get
        {
            return _table;
        }
        set
        {
            _table = value;
        }
    }
    public double scanCount
    {
        get
        {
            return _scanCount;
        }
        set
        {
            _scanCount = value;
        }
    }
    public double logicalreads
    {
        get
        {
            return _logicalreads;
        }
        set
        {
            _logicalreads = value;
        }
    }