WPF之行为(Behavior)

行为

行为的用法有些类似触发器的效果，但是触发器一般只能适用同一种的控件；而一个行为可以用在不同控件下（指定相同的父类）；

下面实现鼠标移入指定控件的时候发生高亮显示：

namespace MyWpf.CommonService
{
    /// <summary>
    /// FrameworkElement的派生类下的控件元素都会触发这个行为
    /// </summary>
    public class EffectBehavior : Behavior<FrameworkElement>
    {
        protected override void OnAttached()
        {
            base.OnAttached();
            //关联鼠标移入移出的事件
            AssociatedObject.MouseMove += AssociatedObject_MouseMove;
            AssociatedObject.MouseLeave += AssociatedObject_MouseLeave;
        }
        /// <summary>
        /// 鼠标移出事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void AssociatedObject_MouseLeave(object sender, System.Windows.Input.MouseEventArgs e)
        {
            var element = sender as FrameworkElement;
            element.Effect = (Effect)new DropShadowEffect() { Color = Colors.Transparent, ShadowDepth = 0 };
        }
        /// <summary>
        /// 鼠标移入事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void AssociatedObject_MouseMove(object sender, System.Windows.Input.MouseEventArgs e)
        {
            var element = sender as FrameworkElement;
            //鼠标移入时候的颜色设置
            element.Effect = (Effect)new DropShadowEffect() { Color = Colors.Red, ShadowDepth = 0 };
        }

        /// <summary>
        /// 解除关联的事件
        /// </summary> 
        protected override void OnDetaching()
        {
            base.OnDetaching();
            AssociatedObject.MouseMove -= AssociatedObject_MouseMove;
            AssociatedObject.MouseLeave -= AssociatedObject_MouseLeave;
        }



    }
}

 

xaml：

<UserControl x:Class="MyWpf.MyBehavior"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:MyWpf.CommonService"
             xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
             mc:Ignorable="d" 
             d:DesignHeight="450" d:DesignWidth="800">
    <Grid>
        <StackPanel>
            <TextBox Width="100" Height="30" Margin="40">
                <i:Interaction.Behaviors>
                    <local:EffectBehavior/>
                </i:Interaction.Behaviors>
            </TextBox>
            <Button Width="100" Height="30" Margin="40">
                <i:Interaction.Behaviors>
                    <local:EffectBehavior/>
                </i:Interaction.Behaviors>
            </Button>
        </StackPanel>
    </Grid> 
</UserControl>

 

结果：