Wpf datagrid always show scrollbar and fill up the space

How can I make a DataGrid to fill up the space and show the vertical scrollbar, even if it has only 10 Rows?

This is the current code:

<UserControl xmlns:Wpf="clr-namespace:Microsoft.Web.WebView2.Wpf;assembly=Microsoft.Web.WebView2.Wpf"  x:Class="myclass.uccontrol"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             mc:Ignorable="d" 
             Focusable="True"
             d:DesignHeight="10000" d:DesignWidth="1049">

    <UserControl.Resources>          
    </UserControl.Resources>

    <Grid VerticalAlignment="Top">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*" />               
        </Grid.ColumnDefinitions>

        <DockPanel >
            <DataGrid Name="dataGrid"
                      AutoGenerateColumns="False"
                      ScrollViewer.CanContentScroll="True" 
                      ScrollViewer.VerticalScrollBarVisibility="Auto"
                      ScrollViewer.HorizontalScrollBarVisibility="Auto"  
                      HorizontalAlignment="Stretch"
                      VerticalAlignment="Stretch">

                <DataGrid.Columns>    
                    <DataGridTextColumn Header = " Name" Binding = "{Binding Name, Mode=OneWay}" SortMemberPath="Name" />
                    <DataGridTextColumn Width="*" Header = " Date" Binding = "{Binding Date, StringFormat=\{0:d\}, Mode=OneWay}" SortMemberPath="DocumentDate" />    
                </DataGrid.Columns>
            </DataGrid>
        </DockPanel>         
    </Grid>
</UserControl>

>Solution :

The <Grid VerticalAlignment="Top"> declaration make the parent grid to try to take as little as possible vertical space. Remove the VerticalAlignment="Top" declaration.

To display the vertical scroll bar use VerticalScrollBarVisibility="Visible" and remove the ScrollViewer.* properties.

By the way, in the provided code:

• the DockPanel is useless.
• the Grid is useless. But I will keep it, maybe there is something else, and it’s related to the question.
• HorizontalAlignment="Stretch" and VerticalAlignment="Stretch" are useless (Stretch is the default value).
• You can collapse some empty tags.

The code should like this:

<UserControl x:Class="myclass.uccontrol"
             xmlns:Wpf="clr-namespace:Microsoft.Web.WebView2.Wpf;assembly=Microsoft.Web.WebView2.Wpf"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             mc:Ignorable="d" 
             Focusable="True"
             d:DesignHeight="10000" d:DesignWidth="1049">

    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*" />               
        </Grid.ColumnDefinitions>

        <DataGrid Name="dataGrid"
                  AutoGenerateColumns="False"                  
                  VerticalScrollBarVisibility="Visible">

            <DataGrid.Columns>    
                <DataGridTextColumn Header=" Name" Binding="{Binding Name, Mode=OneWay}" SortMemberPath="Name" />
                <DataGridTextColumn Width="*" Header = " Date" Binding="{Binding Date, StringFormat=\{0:d\}, Mode=OneWay}" SortMemberPath="DocumentDate" />    
            </DataGrid.Columns>
        </DataGrid>
    </Grid>
</UserControl>

Notes: The bottom part of the data grid will be gray, you can change this with the Background property. If you want empty lines, try this.