社区 › 安全 › Github Copilot 实战: 从零开始用AI写一个OCR工具 (2)

坟菊 发表于 2025-5-30 19:48:49

Github Copilot 实战: 从零开始用AI写一个OCR工具 (2)

源码

https://github.com/densen2014/Blazor100/tree/master/AI/MiOcr
点击图片区域不需要选择图片

要移除“点击图片区域选择图片”的功能，只需删除或注释掉 ImageBorder_MouseLeftButtonUp 方法及其在 XAML 中的事件绑定。
操作步骤如下：

[*]删除 C# 事件处理方法
在 MainWindow.xaml.cs 中，删除如下方法：
// 点击图片区域也可选择图片
private void ImageBorder_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
    SelectImageButton_Click(sender, e);
}
[*]移除 XAML 事件绑定
在 MainWindow.xaml 中，找到绑定了 MouseLeftButtonUp="ImageBorder_MouseLeftButtonUp" 的控件（通常是或 <img>），将该属性删除。例如：
改为:
这样，点击图片区域将不会再弹出选择图片对话框，拖放、粘贴等功能不受影响。
DrawOcrResultsOnImage 画出的区域支持鼠标右键复制文本

先上图:

要让 DrawOcrResultsOnImage 画出的区域支持鼠标右键复制文本，推荐的 WPF 实现方式如下：

[*]记录每个识别区域的多边形和文本，用于命中测试。
[*]在 MainImage 上监听鼠标右键事件，判断鼠标是否在某个区域内。
[*]弹出右键菜单，点击“复制文本”即可将对应文本复制到剪贴板。
下面是详细实现步骤：

[*]定义识别区域数据结构
在 MainWindow 类中添加：
private List<(Geometry geometry, string text)> _ocrRegions = new();
[*]修改 DrawOcrResultsOnImage，记录区域
private BitmapSource DrawOcrResultsOnImage(BitmapImage? image, PaddleOcrResult result)
{
    if (image == null) return null!;
    int width = image.PixelWidth;
    int height = image.PixelHeight;

    _ocrRegions.Clear(); // 清空旧的区域

    var visual = new DrawingVisual();
    using (var dc = visual.RenderOpen())
    {
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>dc.DrawImage(image, new Rect(0, 0, width, height));
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>var pen = new Pen(Brushes.Red, 2);
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>var typeface = new Typeface("Arial");
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>foreach (var region in result.Regions)
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>{
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var vertices = region.Rect.Points();
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var points = vertices.Select(p => new System.Windows.Point(p.X, p.Y)).ToArray();

<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    // 绘制多边形
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var figure = new PathFigure(points, new[] { new PolyLineSegment(points.Skip(1), true) }, true);
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var geometry = new PathGeometry(new[] { figure });
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    dc.DrawGeometry(null, pen, geometry);

<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    // 记录区域和文本
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    _ocrRegions.Add((geometry, region.Text));

<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    // 绘制文字
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var formattedText = new FormattedText(
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>region.Text,
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>System.Globalization.CultureInfo.CurrentCulture,
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>FlowDirection.LeftToRight,
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>typeface,
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>20,
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>Brushes.Yellow,
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>1.25);
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    dc.DrawText(formattedText, new System.Windows.Point(region.Rect.Center.X, region.Rect.Center.Y));
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>}
    }
    var bmp = new RenderTargetBitmap(width, height, 96, 96, PixelFormats.Pbgra32);
    bmp.Render(visual);
    bmp.Freeze();
    return bmp;
}
[*]监听 MainImage 的鼠标右键事件
在 MainWindow.xaml 的增加：

[*]实现右键菜单和复制逻辑
在 MainWindow.xaml.cs 添加：
private void MainImage_MouseRightButtonUp(object sender, MouseButtonEventArgs e)
{
    var pos = e.GetPosition(MainImage);

    // 需要将控件坐标映射到图片像素坐标
    if (_currentImage == null || _ocrRegions.Count == 0) return;

    // 计算缩放比例和偏移
    var imgRect = new Rect(0, 0, _currentImage.PixelWidth, _currentImage.PixelHeight);
    var ctrlRect = new Rect(0, 0, MainImage.ActualWidth, MainImage.ActualHeight);
    var scale = Math.Min(ctrlRect.Width / imgRect.Width, ctrlRect.Height / imgRect.Height);
    var offsetX = (ctrlRect.Width - imgRect.Width * scale) / 2;
    var offsetY = (ctrlRect.Height - imgRect.Height * scale) / 2;
    var imgX = (pos.X - offsetX) / scale;
    var imgY = (pos.Y - offsetY) / scale;
    var imgPoint = new System.Windows.Point(imgX, imgY);

    // 命中测试
    foreach (var (geometry, text) in _ocrRegions)
    {
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>if (geometry.FillContains(imgPoint))
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>{
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    // 弹出右键菜单
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var menu = new ContextMenu();
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var item = new MenuItem { Header = "复制文本" };
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    item.Click += (s, args) => Clipboard.SetText(text);
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    menu.Items.Add(item);
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    menu.IsOpen = true;
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    break;
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>}
    }
}说明
•        支持图片缩放/居中情况下的坐标映射。
•        只在点击到识别区域时弹出“复制文本”菜单。
•        复制后可直接粘贴到其他地方。
如需支持多语言或批量复制，可扩展菜单项。此方案适用于 WPF，且不会影响拖放、粘贴等原有功能。
支持鼠标左键按下拖动多选区域复制文本

效果图:

你可以通过以下方式支持鼠标左键拖动框选多个 OCR 区域并复制文本：

[*]鼠标左键按下时记录起点，拖动时绘制选框，松开时判断与哪些 OCR 区域相交，弹出菜单可复制所有命中的文本。
[*]需要在 MainWindow 中维护选框状态，并在 MainImage 上处理相关事件。

[*]字段定义
在 MainWindow 类中添加
private System.Windows.Point? _selectStart;
private System.Windows.Point? _selectEnd;
private Rectangle _selectionRect = new Rectangle();
private List<string> _selectedTexts = new();
[*]XAML 增加 Canvas 覆盖层
在 MainWindow.xaml 的图片区域外包一层 Grid，并在其上放置一个 Canvas 用于绘制选框：
<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>
[*]鼠标事件实现
在 MainWindow.xaml.cs 添加：
private void MainImage_MouseLeftButtonDown(object sender, MouseButtonEventArgs e){    if (_currentImage == null) return;    _selectStart = e.GetPosition(MainImage);    _selectEnd = null;    _selectedTexts.Clear();    OverlayCanvas.Children.Clear();    MainImage.CaptureMouse();}private void MainImage_MouseMove(object sender, MouseEventArgs e){    if (_selectStart.HasValue && e.LeftButton == MouseButtonState.Pressed)    {<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>_selectEnd = e.GetPosition(MainImage);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>DrawSelectionRectangle();    }}private void MainImage_MouseLeftButtonUp(object sender, MouseButtonEventArgs e){    if (_selectStart.HasValue && _selectEnd.HasValue)    {<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>var rect = GetImageRectFromControlRect(new Rect(_selectStart.Value, _selectEnd.Value));<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>_selectedTexts = _ocrRegions<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    .Where(r => r.geometry.Bounds.IntersectsWith(rect))<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    .Select(r => r.text)<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    .ToList();<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>if (_selectedTexts.Count > 0)<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>{<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var menu = new ContextMenu();<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var item = new MenuItem { Header = $"复制所选文本（{_selectedTexts.Count}）" };<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    item.Click += (s, args) => Clipboard.SetText(string.Join(Environment.NewLine, _selectedTexts));<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    menu.Items.Add(item);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    menu.IsOpen = true;<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>}    }    _selectStart = null;    _selectEnd = null;    OverlayCanvas.Children.Clear();    MainImage.ReleaseMouseCapture();}private void DrawSelectionRectangle(){    OverlayCanvas.Children.Clear();    if (_selectStart.HasValue && _selectEnd.HasValue)    {<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>var rect = new Rect(_selectStart.Value, _selectEnd.Value);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>var r = new System.Windows.Shapes.Rectangle<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>{<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    Stroke = Brushes.Blue,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    StrokeThickness = 2,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    Fill = new SolidColorBrush(Color.FromArgb(40, 0, 0, 255)),<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    Width = rect.Width,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    Height = rect.Height<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>};<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>Canvas.SetLeft(r, rect.Left);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>Canvas.SetTop(r, rect.Top);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>OverlayCanvas.Children.Add(r);    }}
[*]坐标映射辅助方法
添加一个方法，将控件坐标的选框映射到图片像素坐标：
private Rect GetImageRectFromControlRect(Rect ctrlRect)
{
    if (_currentImage == null) return Rect.Empty;
    var imgRect = new Rect(0, 0, _currentImage.PixelWidth, _currentImage.PixelHeight);
    var ctrlActual = new Rect(0, 0, MainImage.ActualWidth, MainImage.ActualHeight);
    var scale = Math.Min(ctrlActual.Width / imgRect.Width, ctrlActual.Height / imgRect.Height);
    var offsetX = (ctrlActual.Width - imgRect.Width * scale) / 2;
    var offsetY = (ctrlActual.Height - imgRect.Height * scale) / 2;

    // 映射到图片坐标
    double x1 = (ctrlRect.Left - offsetX) / scale;
    double y1 = (ctrlRect.Top - offsetY) / scale;
    double x2 = (ctrlRect.Right - offsetX) / scale;
    double y2 = (ctrlRect.Bottom - offsetY) / scale;
    return new Rect(new System.Windows.Point(x1, y1), new System.Windows.Point(x2, y2));
}
[*]说明
•        支持拖动框选，松开后弹出菜单复制所有命中的文本。
•        支持图片缩放和居中。
•        右键单选依然可用。
如需高亮选中区域，可在 DrawOcrResultsOnImage 中根据 _selectedTexts 高亮对应区域。此方案适用于 WPF，且不会影响原有功能。
如何在选框内显示选中的文本内容？

图同上
在 WPF 中，如果你想在拖动选框时在选框内实时显示选中的文本内容，可以在 DrawSelectionRectangle 方法中，除了绘制矩形，还绘制文本。
实现思路如下：


[*]实时获取选框内的文本
在 DrawSelectionRectangle 方法中，获取当前选框对应图片区域的文本：
private void DrawSelectionRectangle(){    OverlayCanvas.Children.Clear();    if (_selectStart.HasValue && _selectEnd.HasValue)    {<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>var rect = new Rect(_selectStart.Value, _selectEnd.Value);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>var r = new System.Windows.Shapes.Rectangle<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>{<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    Stroke = Brushes.Blue,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    StrokeThickness = 2,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    Fill = new SolidColorBrush(Color.FromArgb(40, 0, 0, 255)),<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    Width = rect.Width,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    Height = rect.Height<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>};<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>Canvas.SetLeft(r, rect.Left);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>Canvas.SetTop(r, rect.Top);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>OverlayCanvas.Children.Add(r);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>// 获取选框对应图片坐标的区域<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>var imgRect = GetImageRectFromControlRect(rect);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>var selectedTexts = _ocrRegions<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    .Where(region => region.geometry.Bounds.IntersectsWith(imgRect))<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    .Select(region => region.text)<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    .ToList();<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>if (selectedTexts.Count > 0)<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>{<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    // 在选框内绘制文本<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var text = string.Join(Environment.NewLine, selectedTexts);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    var tb = new TextBlock<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    {<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>Text = text,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>Foreground = Brushes.Black,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>Background = new SolidColorBrush(Color.FromArgb(180, 255, 255, 255)),<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>FontSize = 16,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>TextWrapping = TextWrapping.Wrap,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>Width = r.Width - 8,<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid><Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>Padding = new Thickness(4)<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    };<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    Canvas.SetLeft(tb, rect.Left + 4);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    Canvas.SetTop(tb, rect.Top + 4);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>    OverlayCanvas.Children.Add(tb);<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>}    }}
[*]说明
•        这样拖动时，选框内会实时显示所有被选中的文本内容。
•        TextBlock 的宽度和位置做了适当缩进，避免与边框重叠。
•        若文本较多，TextWrapping 可自动换行。
[*]注意事项
•        如果选框很小，文本可能显示不全，可根据需要调整字体或最小宽高。
•        若要美观，可进一步美化 TextBlock 的样式。
在执行ocr之前显示图片, 然后显示一个正在处理的提示, 提升客户体验

效果图:
https://img2024.cnblogs.com/blog/1980213/202505/1980213-20250527011519803-1551117544.png
你可以在执行 OCR 前先显示图片，然后在图片上方显示一个“正在处理...”的提示，OCR 完成后再隐藏提示。
推荐做法是在 XAML 中添加一个覆盖层（如 TextBlock 或 Border），通过代码控制其可见性。


[*]XAML 增加处理提示层
在 MainWindow.xaml 的图片区域 Grid 内，<img> 和之后添加：

[*]C# 控制提示显示/隐藏
在 MainWindow.xaml.cs 的 RunOcrAndDraw 前后控制提示：
private async Task RunOcrAndDraw(byte[] imageBytes){    // 先显示图片    ProcessingText.Visibility = Visibility.Visible;    await Task.Delay(100); // 确保UI刷新    var ocr = new PaddleOCRService();    var results = await ocr.StartOCR(imageBytes);    ProcessingText.Visibility = Visibility.Collapsed;    if (results.strings == null || results.strings.Count == 0)    {<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>OcrTextBox.Text = "未识别到文本";<Grid>
    <Image x:Name="MainImage" Stretch="Uniform"
         MouseLeftButtonDown="MainImage_MouseLeftButtonDown"
         MouseMove="MainImage_MouseMove"
         MouseLeftButtonUp="MainImage_MouseLeftButtonUp"
         MouseRightButtonUp="MainImage_MouseRightButtonUp"/>
    <Canvas x:Name="OverlayCanvas" IsHitTestVisible="False"/>
</Grid>return;    }    OcrTextBox.Text = string.Join(Environment.NewLine, results.result.Regions.Select(r => r.Text));    var drawed = DrawOcrResultsOnImage(_currentImage, results.result);    MainImage.Source = drawed;}
[*]说明
•        这样图片会立即显示，提示“正在处理...”会覆盖在图片上，OCR 完成后自动隐藏。
•        await Task.Delay(100); 可确保 UI 有机会刷新，防止提示未及时显示。
•        你可以根据需要调整提示样式和位置。
这样即可显著提升用户体验，避免界面卡顿或无响应的错觉。
在选框内绘制文本 出现了错误System.ArgumentException:““-8”不是属性“Width”的有效值。”

你遇到的错误：
System.ArgumentException: “-8”不是属性“Width”的有效值。
原因是：
当选框很小时，r.Width - 8 变成了负数，TextBlock.Width 不能为负。

解决方法
在设置 TextBlock.Width 时，确保其为正数（最小为 1 或 0），可用 Math.Max：
Width = Math.Max(1, r.Width - 8),修正后的代码片段：
var tb = new TextBlock
{
    Text = text,
    Foreground = Brushes.Black,
    Background = new SolidColorBrush(Color.FromArgb(180, 255, 255, 255)),
    FontSize = 16,
    TextWrapping = TextWrapping.Wrap,
    Width = Math.Max(1, r.Width - 8),
    Padding = new Thickness(4)
};建议：
你也可以判断选框宽高过小时不显示文本，避免体验异常。
这样即可避免该异常，选框很小时不会再报错。

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