WPF 通过名称查找属性（DependencyProperty）

Posted 2021-02-20 lonelyxmas

原文:WPF 通过名称查找属性（DependencyProperty）

使用名称来查找DependencyProperty。

如果有这样的需求，则是需要通过DependencyPropertyDescriptor来查找。

通常是使用附加属性或者依赖属性的方法。

下面给出附加属性的例子：

 

 这个是注册附加属性，利用string来输入要查找的属性

        

        public static readonly DependencyProperty AniInvokeParameterProperty = DependencyProperty.RegisterAttached("AniInvokeParameter", typeof(string), typeof(AniInvoke));

        public static void SetAniInvokeParameter(DependencyObject d, string value) => d.SetValue(AniInvokeParameterProperty, value);

        public static string GetAniInvokeParameter(DependencyObject d) => (string)d.GetValue(AniInvokeParameterProperty);

 

具体DependencyPropertyDescriptor使用

 public static readonly DependencyProperty AniInvokePropery = DependencyProperty.RegisterAttached("AniInvoke", typeof(AnimationTimeline), typeof(AniInvoke), new PropertyMetadata(null, AniInvokeCallBack));

        public static void SetAniInvoke(DependencyObject d, AnimationTimeline value) => d.SetValue(AniInvokePropery, value);

        public static AnimationTimeline GetAniInvoke(DependencyObject d) => (AnimationTimeline)d.GetValue(AniInvokePropery);

        private static void AniInvokeCallBack(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var t = d as FrameworkElement;

            var dpName = t.GetValue(AniInvokeParameterProperty) as string;

           
            if (!string.IsNullOrWhiteSpace(dpName))
            {
                var dpd = DependencyPropertyDescriptor.FromName(dpName, t.GetType(), t.GetType());

                var property = dpd.DependencyProperty;

                var ani = (AnimationTimeline)e.NewValue;

                if (property != null && ani != null)

                    t.BeginAnimation(property, ani);
            }
           
        }

 

Xaml 代码

<Grid Grid.Row="1" Background="Red"  ado:AniInvoke.AniInvokeParameter="Width"  >
            <ado:AniInvoke.AniInvoke>
                <DoubleAnimationUsingKeyFrames>
                    <EasingDoubleKeyFrame Value="30" KeyTime="00:00:02">
                        <EasingDoubleKeyFrame.EasingFunction>
                            <CubicEase EasingMode="EaseOut"/>
                        </EasingDoubleKeyFrame.EasingFunction>
                    </EasingDoubleKeyFrame>
                    <EasingDoubleKeyFrame Value="500" KeyTime="00:00:06">
                        <EasingDoubleKeyFrame.EasingFunction>
                            <BounceEase Bounces="5" EasingMode="EaseOut"/>
                        </EasingDoubleKeyFrame.EasingFunction>
                    </EasingDoubleKeyFrame>
                </DoubleAnimationUsingKeyFrames>
            </ado:AniInvoke.AniInvoke>
</Grid>