佈局問題與可視c＃

我在Visual Studio 2017（Visual C＃）上創建一個簡單的WPF應用程序。我有這樣的形式：佈局問題與可視c＃

<Window x:Class="HelloWPFApp.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:HelloWPFApp" 
     mc:Ignorable="d" 
     Title="Greetings" Height="350" Width="525"> 
    <Grid Height="319" VerticalAlignment="Bottom"> 
     <Grid.RowDefinitions> 
      <RowDefinition Height="192*"/> 
      <RowDefinition Height="41*"/> 
      <RowDefinition Height="86*"/> 
     </Grid.RowDefinitions> 
     <Grid.ColumnDefinitions> 
      <ColumnDefinition/> 
     </Grid.ColumnDefinitions> 
     <TextBlock HorizontalAlignment="Center" TextWrapping="Wrap" Text="Select a message option and then choose the Display button." VerticalAlignment="Center" Height="16" Width="329" Margin="102,131,86,45"/> 
     <RadioButton x:Name="rbHello" Content="Hello" HorizontalAlignment="Left" Margin="102,2,0,0" VerticalAlignment="Top" Height="15" Width="47" Grid.Row="1"/> 
     <RadioButton x:Name="rbGoodbye" Content="Goodbye" HorizontalAlignment="Left" Margin="337,2,0,0" VerticalAlignment="Top" Height="15" Width="67" Grid.Row="1"/> 
     <Button Content="Display" HorizontalAlignment="Left" VerticalAlignment="Top" Width="75" Margin="231,2,0,0" Click="Button_Click" Height="20" Grid.Row="2"/> 
    </Grid> 
</Window>

，這是預覽：