c#2_17.xaml

<Window x:Class="TicTacToe.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:TicTacToe"
        mc:Ignorable="d"
        ResizeMode="NoResize"
        Title="Tic Tac Toe" Height="600" Width="500">
    <Window.Resources>

        <Style TargetType="Label">
            <Setter Property="Background" Value="LightGray"/>
            <Setter Property="FontSize" Value="20" />
            <Setter Property="VerticalContentAlignment" Value="Center" />
        </Style>

        <Style TargetType="Button" x:Key="CellStyle">
            <Setter Property="Background" Value="White"/>
            <Setter Property="BorderThickness" Value="2"/>
            <Setter Property="BorderBrush" Value="DarkGray" />
            <Setter Property="FontSize" Value="65" />
        </Style>

        <Style TargetType="Button" x:Key="ButtonStyle">
            <Setter Property="Background" Value="PaleGreen"/>
            <Setter Property="FontSize" Value="20" />
        </Style>

    </Window.Resources>
    <Grid>

        <Grid.RowDefinitions>
            <RowDefinition Height="50" />
            <RowDefinition Height="*" />
            <RowDefinition Height="50" />
        </Grid.RowDefinitions>

        <Label Grid.Row="0" Name="GameInformation"></Label>

        <Grid Grid.Row="1">

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

            <Grid.RowDefinitions>
                <RowDefinition Height="*" />
                <RowDefinition Height="*" />
                <RowDefinition Height="*" />
            </Grid.RowDefinitions>

            <Button Click="Button_Click" Name="Button0_0" Grid.Column="0" Grid.Row="0" Style="{StaticResource CellStyle}" />
            <Button Click="Button_Click" Name="Button0_1" Grid.Column="0" Grid.Row="1" Style="{StaticResource CellStyle}" />
            <Button Click="Button_Click" Name="Button0_2" Grid.Column="0" Grid.Row="2" Style="{StaticResource CellStyle}" />

            <Button Click="Button_Click" Name="Button1_0" Grid.Column="1" Grid.Row="0" Style="{StaticResource CellStyle}" />
            <Button Click="Button_Click" Name="Button1_1" Grid.Column="1" Grid.Row="1" Style="{StaticResource CellStyle}" />
            <Button Click="Button_Click" Name="Button1_2" Grid.Column="1" Grid.Row="2" Style="{StaticResource CellStyle}" />

            <Button Click="Button_Click" Name="Button2_0" Grid.Column="2" Grid.Row="0" Style="{StaticResource CellStyle}" />
            <Button Click="Button_Click" Name="Button2_1" Grid.Column="2" Grid.Row="1" Style="{StaticResource CellStyle}" />
            <Button Click="Button_Click" Name="Button2_2" Grid.Column="2" Grid.Row="2" Style="{StaticResource CellStyle}" />
        </Grid>

        <Button Click="StartButton_Click" Name="StartButton" Grid.Row="2" Style="{StaticResource ButtonStyle}">Neues Spiel starten</Button>

    </Grid>

</Window>