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public class ScaleBehavior : Behavior<FrameworkElement>
{protected override void OnAttached(){base.OnAttached();AssociatedObject.MouseWheel += AssociatedObject_MouseWheel;}private void AssociatedObject_MouseWheel(object sender, System.Windows.Input.MouseWheelEventArgs e){//首次滚动时，判断RenderTransform的类型是否为ScaleTransformif (!(AssociatedObject.RenderTransform is ScaleTransform)){AssociatedObject.RenderTransform = new ScaleTransform(){CenterX = AssociatedObject.ActualWidth / 2,CenterY = AssociatedObject.ActualHeight / 2,};}var transform = AssociatedObject.RenderTransform as ScaleTransform;double scale = e.Delta * 0.001;transform.ScaleX += scale;transform.ScaleY += scale;}protected override void OnDetaching(){base.OnDetaching();AssociatedObject.MouseWheel -= AssociatedObject_MouseWheel;}        
}

public class ScaleBehavior : Behavior<FrameworkElement>
{// 当行为附加到元素时注册鼠标滚轮事件 protected override void OnAttached(){base.OnAttached();AssociatedObject.MouseWheel += AssociatedObject_MouseWheel;// [!] 未校验父容器尺寸变化（ActualWidth/Height可能动态更新）}// 鼠标滚轮事件处理：动态缩放元素 private void AssociatedObject_MouseWheel(object sender, MouseWheelEventArgs e){// 首次滚动时强制创建缩放变换（可能覆盖原有变换链）if (!(AssociatedObject.RenderTransform is ScaleTransform)){AssociatedObject.RenderTransform = new ScaleTransform(){// 设置缩放中心为元素几何中心 CenterX = AssociatedObject.ActualWidth / 2, // [!] 未监听ActualWidth变化 CenterY = AssociatedObject.ActualHeight / 2 };}var transform = AssociatedObject.RenderTransform as ScaleTransform;// 计算缩放增量（Delta=120为滚轮单位，固定0.001系数）double scale = e.Delta * 0.001; // [!] 未提供缩放速度可配置化 // 同步修改X/Y轴缩放比例（可能导致非等比缩放）transform.ScaleX += scale; // [!] 无最小/最大值限制 transform.ScaleY += scale;}// 行为分离时解除事件绑定 protected override void OnDetaching(){base.OnDetaching();AssociatedObject.MouseWheel -= AssociatedObject_MouseWheel;// [!] 未还原RenderTransform原始状态 }
}

graph TD A[行为附加到元素] --> B[注册MouseWheel事件]B --> C{用户滚动鼠标滚轮}C -->|首次滚动| D[创建ScaleTransform并设置中心点]C -->|非首次| E[获取现有ScaleTransform]D --> F[计算缩放增量]E --> F F --> G[更新ScaleX/ScaleY值]H[行为分离] --> I[解除事件绑定]classDef risk fill:#FFF3E0,stroke:#FFA726;class D,G risk style F stroke:#4CAF50,stroke-width:2px 

2. 增强版代码示例

// 支持动画与变换组合的改进实现 
public class EnhancedScaleBehavior : Behavior<FrameworkElement>
{protected override void OnAttached(){// 初始化组合变换（保留原有变换）if (AssociatedObject.RenderTransform is not TransformGroup){AssociatedObject.RenderTransform = new TransformGroup {Children = { new ScaleTransform(), new RotateTransform() }};}// 监听尺寸变化更新缩放中心 AssociatedObject.SizeChanged += (s, e) => (AssociatedObject.RenderTransform as TransformGroup).Children.OfType<ScaleTransform>().First().CenterX = e.NewSize.Width / 2;}private void AnimateScale(double delta){var scaleTransform = (AssociatedObject.RenderTransform as TransformGroup).Children.OfType<ScaleTransform>().First();//