C# 如何设置列'；s宽度是否仅使用可用空间？

我在另一个datagrid的行详细信息中有一个datagrid

一列包含注释（

p\u COMMENT

）。注释的长度可以为几百个字符

我已将此列的单元格设置为通过元素样式包装其文本：

<Style x:Key="GridCellWrapping" TargetType="TextBlock">
    <Setter Property="TextBlock.TextWrapping" Value="Wrap"/>
</Style>

<Expander Header="Nachweispruefung" IsExpanded="{Binding showNachweispruefung}">
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition/>
            <ColumnDefinition/>
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
            <RowDefinition/>
            <RowDefinition/>
        </Grid.RowDefinitions>

        <DataGrid Grid.Row="0" Grid.ColumnSpan="2" Margin="5"
                  ItemsSource="{Binding Nachweispruefung}"
                  CanUserAddRows="False"
                  CanUserDeleteRows="False"
                  IsReadOnly="True"
                  SelectionMode="Single"
                  AutoGenerateColumns="False"
                  SelectedValuePath="ID"
                  SelectedValue="{Binding selectedID}"
                  RowDetailsVisibilityMode="VisibleWhenSelected"
                  PreviewMouseWheel="Relay_PreviewMouseWheel"
                  HorizontalAlignment="Stretch"
                  HorizontalContentAlignment="Stretch"
                  HorizontalScrollBarVisibility="Disabled">
            <DataGrid.Columns>
                <DataGridTextColumn Width="*" Binding="{Binding PaketeString}" Header="Pakete" ElementStyle="{StaticResource GridCellPadding}" IsReadOnly="True"/>
            </DataGrid.Columns>

            <DataGrid.RowDetailsTemplate>
                <DataTemplate>
                    <Grid Background="LightGray">
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="*"/>
                        </Grid.ColumnDefinitions>
                        <Grid.RowDefinitions>
                            <RowDefinition/>
                            <RowDefinition/>
                            <RowDefinition/>
                            <RowDefinition/>
                            <RowDefinition/>
                            <RowDefinition/>
                        </Grid.RowDefinitions>

                        <!--Pruefung-->
                        <GroupBox Header="Pruefkriterien" Margin="5" Padding="5" Grid.Row="2" BorderBrush="Black" Background="Black">
                            <StackPanel>
                                <DataGrid ItemsSource="{Binding Pruefungen}"
                                          CanUserAddRows="False"
                                          CanUserDeleteRows="False"
                                          IsReadOnly="True"
                                          SelectionMode="Single"
                                          AutoGenerateColumns="False"
                                          SelectedValuePath="ID"
                                          SelectedValue="{Binding DataContext.selectedNwpPruefungID, RelativeSource={RelativeSource AncestorType={x:Type Page}}}"
                                          PreviewMouseWheel="Relay_PreviewMouseWheel"
                                          HorizontalAlignment="Stretch"
                                          HorizontalContentAlignment="Stretch">
                                    <DataGrid.Columns>
                                        <DataGridTextColumn Width="Auto" Binding="{Binding P_ITEM}" Header="Pruefgegenstand"/>
                                        <DataGridTextColumn Width="Auto" Binding="{Binding P_COUNT}" Header="Anzahl"/>
                                        <DataGridTextColumn Width="Auto" Binding="{Binding P_TIME}" Header="Zeitraum in&#x0a;Monaten"/>
                                        <DataGridTextColumn Width="Auto" Binding="{Binding P_COMMENT}" Header="Kommentar" ElementStyle="{StaticResource GridCellWrapping}"/>
                                        <DataGridCheckBoxColumn Width="Auto" Binding="{Binding P_ALTERNATIV, Mode=OneWay}" Header="Alternative"/>
                                    </DataGrid.Columns>
                                </DataGrid>

                            </StackPanel>
                        </GroupBox>

                    </Grid>
                </DataTemplate>
            </DataGrid.RowDetailsTemplate>
        </DataGrid>
    </Grid>
</Expander>