WPF-事件触发器

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我是靠谱客的博主含蓄火龙果，这篇文章主要介绍WPF-事件触发器，现在分享给大家，希望可以做个参考。

触发器基本上使您能够更改属性值或根据属性值采取行动。因此，它允许您动态地更改控件的外观和/或行为，而无需创建新的控件。
当满足某些条件时，触发器用于更改任何给定属性的值。触发器通常在应用于特定控件的样式或文档根中定义。有三种类型的触发器
• 属性触发器
• 数据触发器
• 事件触发器

事件触发器
当特定事件被触发时，事件触发器执行一些操作。它通常用来完成一些动画控制，如双数字，彩色动画等。在下面的例子中，我们将创建一个简单的按钮。当点击事件被触发时，它将扩展按钮的宽度和高度。

复制代码

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<Window x:Class="trigger.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:trigger"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <Button Content = "Click Me" Width = "60" Height = "30">
            <Button.Triggers>
                <EventTrigger RoutedEvent = "Button.Click">
                    <EventTrigger.Actions>
                        <BeginStoryboard>
                            <Storyboard>
                                <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty = 
                           "Width" Duration = "0:0:4">
                                    <LinearDoubleKeyFrame Value = "60" KeyTime = "0:0:0"/>
                                    <LinearDoubleKeyFrame Value = "120" KeyTime = "0:0:1"/>
                                    <LinearDoubleKeyFrame Value = "200" KeyTime = "0:0:2"/>
                                    <LinearDoubleKeyFrame Value = "300" KeyTime = "0:0:3"/>
                                </DoubleAnimationUsingKeyFrames>
                                <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty = "Height" 
                           Duration = "0:0:4">
                                    <LinearDoubleKeyFrame Value = "30" KeyTime = "0:0:0"/>
                                    <LinearDoubleKeyFrame Value = "40" KeyTime = "0:0:1"/>
                                    <LinearDoubleKeyFrame Value = "80" KeyTime = "0:0:2"/>
                                    <LinearDoubleKeyFrame Value = "150" KeyTime = "0:0:3"/>
                                </DoubleAnimationUsingKeyFrames>
                            </Storyboard>
                        </BeginStoryboard>
                    </EventTrigger.Actions>
                </EventTrigger>
            </Button.Triggers>
        </Button>
    </Grid>
</Window>