当我在C＃中使用inkcanvas1.Strokes.Erase语句时，WPF-InkCanvas StrokeErased事件未触发

问题描述

当我使用inkcanvas1.EditingMode为InkCanvasEditingMode.EraseByPoint时，它正在擦除并且还触发了strokeErased事件。
但是当我通过inkcanvas1.strokes.Erase（）擦除笔划时函数，则不会触发strokeErased事件。
然后如何识别删除的笔画和新创建的笔画。
考虑在我的画布上笔触数以千计。
所以我无法保持所有添加和删除的笔画。 还有其他事件或解决方案吗？

我有以下示例WPF Inkcanvas代码
XAML代码

<Window x:Class="Mywhiteboard.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:Mywhiteboard"
        mc:Ignorable="d"
        WindowState="Maximized"
        Title="MainWindow" >
    <Grid>
        <Grid.RowDeFinitions>
            <RowDeFinition Height="*"></RowDeFinition>
            <RowDeFinition Height="auto"></RowDeFinition>
        </Grid.RowDeFinitions>
        <InkCanvas x:Name="inkcanvas1" Grid.Row="0" strokeErased="inkcanvas1_strokeErased" MouseMove="inkcanvas1_MouseMove"></InkCanvas>
        <StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Center">
            <Button Width="100" Height="50" Background="WhiteSmoke" Content="Draw" Click="drawInkClick"></Button>
            <Button Width="100" Height="50" Background="WhiteSmoke" Content="Erase by Point" Click="EraseByPointsClick"></Button>
            <Button Width="100" Height="50" Background="WhiteSmoke" Content="stroke Erase" Click="strokeEraseClick"></Button>
            <Button Width="100" Height="50" Background="WhiteSmoke" Content="clear all" Click="clearallClick"></Button>
        </StackPanel>
    </Grid>
</Window>

C＃代码后面的代码

public partial class MainWindow : Window
    {
        private bool IsstrokeEraseCalled = false;
        public MainWindow()
        {
            InitializeComponent();
        }
        private void inkcanvas1_strokeErased(object sender,RoutedEventArgs e)
        {
            // why this event is not calling when I use  
            //inkcanvas1.strokes.Erase
        }
        private void EraseByPointsClick(object sender,RoutedEventArgs e)
        {
            inkcanvas1.EditingMode = InkCanvasEditingMode.EraseByPoint;
        }
        private void strokeEraseClick(object sender,RoutedEventArgs e)
        {
            inkcanvas1.EditingMode = InkCanvasEditingMode.Select;
            IsstrokeEraseCalled = !IsstrokeEraseCalled;
        }
        private void clearallClick(object sender,RoutedEventArgs e)
        {
            inkcanvas1.strokes.Clear();
        }
        private void inkcanvas1_MouseMove(object sender,MouseEventArgs e)
        {
            if (IsstrokeEraseCalled)
            {
                Point currentPoint = e.GetPosition((IInputElement)sender);
                List<Point> enumrator = new List<Point>();
                enumrator.Add(new Point(currentPoint.X,currentPoint.Y));
                StylusShape EraseShape = (StylusShape)new RectangleStylusShape(100,100,0);
                inkcanvas1.strokes.Erase(enumrator,EraseShape);
            }
        }

        private void drawInkClick(object sender,RoutedEventArgs e)
        {
            inkcanvas1.EditingMode = InkCanvasEditingMode.Ink;
        }
    }

解决方法

尝试一下

web.config

,

1. 通过inkcanvas1.Strokes.Erase();功能擦除笔划时，默认情况下不会触发 StrokeErased事件。
2. 如果要保持添加和删除的笔划，则可以在inkcanvas1.Strokes.StrokesChanged事件中处理它。
3. 或者您应该处于EraseByPoint模式并使用语句
   inkcanvas1.EraserShape = new RectangleStylusShape(100,100);
4. 如果您的墨水画布上有大量笔触，那么每次维护每个笔划时都很沉重，那么您可以选择使用ProperyData属性为每个笔划添加唯一的ID。

,

用以下代码替换您的StrokeEraseClick事件：

private void StrokeEraseClick(object sender,RoutedEventArgs e)
    {
        inkcanvas1.EditingMode = InkCanvasEditingMode.EraseByPoint;
        inkcanvas1.EraserShape = new RectangleStylusShape(100,100);
        var editMode = inkcanvas1.EditingMode;
        inkcanvas1.EditingMode = InkCanvasEditingMode.None;
        inkcanvas1.EditingMode = editMode;
    }      

它将当前模式保留为InkCanvasEditingMode.EraseByPoint，并允许您擦除定义的区域笔画。每当您使用此方法擦除笔划时，都会触发StrokeErased事件。