WPF(x:Null 使用)

<Window x:Class="TestOfNull.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="x:Null Sample" Height="350" Width="525">
    <Window.Resources>
        <Style x:Key="{x:Type Button}" TargetType="{x:Type Button}" >
            <Setter Property="Width" Value="60" />
            <Setter Property="Height" Value="36" />
            <Setter Property="Margin" Value="5" />
        </Style>
    </Window.Resources>

    <StackPanel >
        <Button Content="OK" />
        <Button Content="OK" />
        <Button Content="OK" />
        <Button Content="OK" Style="{x:Null}" />
    </StackPanel>
</Window>