代码改变世界

WP7备注(14)(ContentPropertyAttribute)

2011-04-28 09:59  血糯米Otomii  阅读(331)  评论(0编辑  收藏  举报

ContentPropertyAttribute主要用于Xaml的简化.

<TextBlock.Foreground>
<RadialGradientBrush>
<RadialGradientBrush.GradientStops>
<GradientStopCollection>
<GradientStop Offset="0" Color="Transparent" />
<GradientStop Offset="1" Color="Red" />
</GradientStopCollection>
</RadialGradientBrush.GradientStops>
</RadialGradientBrush>
</TextBlock.Foreground>

首先剔除GradientStopCollenction

<TextBlock.Foreground>
<RadialGradientBrush>
<RadialGradientBrush.GradientStops>
<GradientStop Offset="0" Color="Transparent" />
<GradientStop Offset="1" Color="Red" />
</RadialGradientBrush.GradientStops>
</RadialGradientBrush>
</TextBlock.Foreground>

其次,因为

[ContentPropertyAttribute("GradientStops", true)]
public abstract class GradientBrush : Brush

所以,可以剔除RadialGradientBrush.GradientStops,变成

<TextBlock.Foreground>
<RadialGradientBrush>
<GradientStop Offset="0" Color="Transparent" />
<GradientStop Offset="1" Color="Red" />
</RadialGradientBrush>
</TextBlock.Foreground>

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又如

[ContentPropertyAttribute("Children", true)]
public abstract class Panel : FrameworkElement

[ContentPropertyAttribute("Content", true)]
public class UserControl : Control

都是给与Xaml元素默认的可省略内部元素标签