<Window x:Class="wpfwindowsmove.毛边窗体"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="毛边窗体" Height="300" Width="300"
        AllowsTransparency="True" WindowStyle="None" Background="Transparent"
        >
    <Grid>
        <Border BorderThickness="1" CornerRadius="50">
            <Border.Background>
                <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                    <GradientStop Color="Green" Offset="0"></GradientStop>
                    <GradientStop Color="Blue" Offset="1"></GradientStop>
                    <GradientStop Color="Yellow"></GradientStop>
                </LinearGradientBrush>
            </Border.Background>
            <Border.BitmapEffect>
                <BlurBitmapEffect></BlurBitmapEffect>
            </Border.BitmapEffect>
           
        </Border>
    </Grid>
</Window>