OpacityMask

是一个掩饰的功能：

OpacityMask在大部分控件中都有的属性，在强调显示会有用。

可以加的笔画众多。下的小例子。

<Window.Background>

        <LinearGradientBrush>

            <GradientStop Offset="0" Color="Red"></GradientStop>

            <GradientStop Offset="1" Color="Green"></GradientStop>

        </LinearGradientBrush>

    </Window.Background>

    <Button Margin="40" FontSize="80">RAJ

        <Button.OpacityMask>

            <LinearGradientBrush EndPoint="0.1,0.1" SpreadMethod="Reflect">

                <GradientStop Offset="0" Color="Gray"></GradientStop>

                <GradientStop Offset="1" Color="Transparent"></GradientStop>

            </LinearGradientBrush>

        </Button.OpacityMask>

    </Button>  

http://s4/middle/3f061265h7662347f55c3&690

<Grid>

        <Image Source="ais245a.jpg" Height="200">

            <Image.OpacityMask>

                <RadialGradientBrush Center="0.5,0.5">

                    <GradientStop Color="#00000000" Offset="1" />

                    <GradientStop Color="#20000000" Offset="0.8" />

                    <GradientStop Color="#FF000000" Offset="0" />

                </RadialGradientBrush>

            </Image.OpacityMask>

        </Image>

    </Grid>

http://s16/middle/3f061265h9fd60cfef7af&690

----------------------其它的画笔信息内容。--------------------

<Label.OpacityMask>
                <LinearGradientBrush StartPoint="0,0.5" EndPoint="0,1">
                    <GradientStop Offset="0.2" Color="Transparent"/>
                    <GradientStop Offset="0.3" Color="Red"/>
                    <GradientStop Offset="0.2" Color="Transparent"/>
                    <GradientStop Offset="0.1" Color="Black"/>
                </LinearGradientBrush>

                <!--加图片-->
                <ImageBrush ImageSource="images/MinBack.jpg" Opacity="0.2"/>

               
            </Label.OpacityMask>