ScreenToGif/Controls/InkCanvasExtended.cs

微信扫码关注公众号，代码整理好后第一时间通知你。

using System.Windows;
using System.Windows.Controls;
using System.Windows.Ink;
using System.Windows.Media;

namespace ScreenToGif.Controls
{
    /// <summary>
    /// InkCanvasControl class extending the InkCanvas class
    /// </summary>
    public class InkCanvasExtended : InkCanvas
    {
        /// <summary>
        /// Gets or set the eraser shape
        /// </summary>
        public new StylusShape EraserShape
        {
            get { return (StylusShape) GetValue(EraserShapeProperty); }
            set { SetValue(EraserShapeProperty, value); }
        }

        // Using a DependencyProperty as the backing store for EraserShape.  
        // This enables animation, styling, binding, etc...
        public static readonly DependencyProperty EraserShapeProperty = DependencyProperty.Register("EraserShape", typeof (StylusShape), typeof (InkCanvasExtended), 
            new UIPropertyMetadata(new RectangleStylusShape(10, 10), OnEraserShapePropertyChanged));

        /// <summary>
        /// Event to handle the property change
        /// </summary>
        /// <param name="d">dependency object</param>
        /// <param name="e">event args</param>
        private static void OnEraserShapePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var canvas = d as InkCanvasExtended;

            if (canvas == null)
                return;

            canvas.EraserShape = (StylusShape) e.NewValue;
            canvas.RenderTransform = new MatrixTransform();
        }
    }
}