Question

我有WritableBitmap图像，我已在图像控件src中设置。我在用户移动选定的文本区域时创建矩形。我还使用PDFtron SDK从PDF文档中获取所选文本。我们从PDF获取WritableBitmap图片。我们必须在线选择文字。

我正在使用此代码绘制屏幕：

System.Drawing.Rectangle rectangle = new System.Drawing.Rectangle((int)Math.Min(_downX, x),
                             (int)Math.Min(_downY, y),
                             (int)Math.Abs(_downX - x),
                             (int)Math.Abs(_downY - y));

System.Drawing.Bitmap myBitmap = new System.Drawing.Bitmap(@"D:\PDF\ScreenDraw\WpfApplication1\WpfApplication1\Image\Capture.PNG");

using (System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(myBitmap))
{
    System.Drawing.Color customColor = System.Drawing.Color.FromArgb(50, System.Drawing.Color.Red);
    System.Drawing.SolidBrush shadowBrush = new System.Drawing.SolidBrush(customColor);
    g.FillRectangles(shadowBrush, new System.Drawing.Rectangle[] { rectangle });
}

//myBitmap.Save(@"D:\PDF\abc.png");
//bitmapSource = new BitmapImage(new Uri(@"D:\PDF\abc.png", UriKind.Absolute));

using (var memory = new System.IO.MemoryStream())
{
    myBitmap.Save(memory, System.Drawing.Imaging.ImageFormat.Png);
    memory.Position = 0;

    var bitmapImage = new BitmapImage();
    bitmapImage.BeginInit();
    bitmapImage.StreamSource = memory;
    bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
    bitmapImage.EndInit();
    Img.Source = bitmapImage;
}

如何选择明文而不是Rect明智的文字？

我必须选择上面图片中显示的文字。

Answer 1

你想要的是不可能的。你有一个位图，并没有神奇地意识到它的文本，没有什么会改变它。虽然并不是说你无能为力。我没有时间提供完整的解决方案，但我可以提供如何实现最佳解决方案的逐步说明。

你能做的是：

文字尺寸定义 - 使用可编辑的X轴和Y轴步进和偏移在图像上叠加网格来创建控件。然后，您将能够使用文本行（Y）校准网格。和字符宽度（X）。这样的事情应该做（我想你会得到一般的想法）：

public int XGridStep
{
    get { return (int)base.GetValue(XGridStepProperty); }
    set
    {
        base.SetValue(XGridStepProperty, value);
        RepaintGrid();
    }
}

public static readonly DependencyProperty XGridStepProperty = DependencyProperty.Register("XGridStepProperty", typeof(int), typeof(PlanLayout), new PropertyMetadata(100));

public int XGridOffset
{
    get { return (int)base.GetValue(XGridOffsetProperty); }
    set
    {
        base.SetValue(XGridOffsetProperty, value);
        RepaintGrid();
    }
}

public static readonly DependencyProperty XGridOffsetProperty = DependencyProperty.Register("XGridOffsetProperty", typeof(int), typeof(PlanLayout), new PropertyMetadata(0));

public bool XGridVisible
{
    get { return (bool)base.GetValue(XGridVisibleProperty); }
    set
    {
        base.SetValue(XGridVisibleProperty, value);
        RepaintGrid();
    }
}

public static readonly DependencyProperty XGridVisibleProperty = DependencyProperty.Register("XGridVisibleProperty", typeof(bool), typeof(PlanLayout), new PropertyMetadata(false));

public int YGridStep
{
    get { return (int)base.GetValue(YGridStepProperty); }
    set
    {
        base.SetValue(YGridStepProperty, value);
        RepaintGrid();
    }
}

public static readonly DependencyProperty YGridStepProperty = DependencyProperty.Register("YGridStepProperty", typeof(int), typeof(PlanLayout), new PropertyMetadata(100));

public int YGridOffset
{
    get { return (int)base.GetValue(YGridOffsetProperty); }
    set
    {
        base.SetValue(YGridOffsetProperty, value);
        RepaintGrid();
    }
}

public static readonly DependencyProperty YGridOffsetProperty = DependencyProperty.Register("YGridOffsetProperty", typeof(int), typeof(PlanLayout), new PropertyMetadata(0));

public bool YGridVisible
{
    get { return (bool)base.GetValue(YGridVisibleProperty); }
    set
    {
        base.SetValue(YGridVisibleProperty, value);
        RepaintGrid();
    }
}

public static readonly DependencyProperty YGridVisibleProperty = DependencyProperty.Register("YGridVisibleProperty", typeof(bool), typeof(PlanLayout), new PropertyMetadata(false));

private void RepaintGrid()
{
    if (!IsEditable)
        return;

    foreach (Line l in _gridXLines)
        content.Children.Remove(l);
    _gridXLines.Clear();
    if (XGridVisible)
        for (int i = XGridOffset; i < content.ActualWidth; i += XGridStep)
        {
            Line line = new Line();
            line.IsHitTestVisible = false;
            line.Stroke = Brushes.Black;
            line.Y1 = 0;
            line.Y2 = content.ActualHeight;
            line.X1 = line.X2 = i;
            if (Math.Abs(line.X1 - content.ActualWidth) < XGridStep * 0.5 || line.X1 < XGridStep * 0.5)
                continue;
            _gridXLines.Add(line);
            content.Children.Add(line);
            Canvas.SetZIndex(line, 0);
        }

    foreach (Line l in _gridYLines)
        content.Children.Remove(l);
    _gridYLines.Clear();
    if (YGridVisible)
        for (int i = YGridOffset; i < content.ActualHeight; i += YGridStep)
        {
            Line line = new Line();
            line.IsHitTestVisible = false;
            line.Stroke = Brushes.Black;
            line.X1 = 0;
            line.X2 = content.ActualWidth;
            line.Y1 = line.Y2 = i;
            if (Math.Abs(line.Y1 - content.ActualHeight) < YGridStep * 0.5 || line.Y1 < YGridStep * 0.5)
                continue;
            _gridYLines.Add(line);
            content.Children.Add(line);
            Canvas.SetZIndex(line, 0);
        }
}

文字选择 - 您现在要做的就是为控件添加“对齐网格”功能。再次，仅供参考：

private void elementWrapper_MouseMove(object sender, System.Windows.Input.MouseEventArgs e)
{
    if (_mouseHandlingMode != MouseHandlingMode.Dragging)
        return;

    SelectableElement element = (SelectableElement)sender;

    Point curContentPoint = e.GetPosition(content);
    //Vector elementDragVector = curContentPoint - _origContentMouseDownPoint;

    _origContentMouseDownPoint = curContentPoint;

    //double destinationLeft = Canvas.GetLeft(element) + elementDragVector.X;
    //double destinationTop = Canvas.GetTop(element) + elementDragVector.Y;
    double destinationLeft = curContentPoint.X - element.ActualWidth / 2;
    double destinationTop = curContentPoint.Y - element.ActualHeight / 2;

    if (SnapToGrid)
    {
        if (XGridVisible)
        {
            foreach (Line l in _gridXLines)
                l.StrokeThickness = 1;

            Line nearest = GetNearestXGridLine((int)curContentPoint.X);

            if (Math.Abs(curContentPoint.X - nearest.X1) < XGridStep * 0.2)
            {
                destinationLeft = nearest.X1 - element.ActualWidth / 2;
                nearest.StrokeThickness = 3;
            }
        }

        if (YGridVisible)
        {
            foreach (Line l in _gridYLines)
                l.StrokeThickness = 1;

            Line nearest = GetNearestYGridLine((int)curContentPoint.Y);

            if (Math.Abs(curContentPoint.Y - nearest.Y1) < YGridStep * 0.2)
            {
                destinationTop = nearest.Y1 - element.ActualHeight / 2;
                nearest.StrokeThickness = 3;
            }
        }
    }

    if (destinationLeft < 0)
        destinationLeft = 0;

    if (destinationLeft > content.ActualWidth - element.ActualWidth)
        destinationLeft = content.ActualWidth - element.ActualWidth;

    if (destinationTop < 0)
        destinationTop = 0;

    if (destinationTop > content.ActualHeight - element.ActualHeight)
        destinationTop = content.ActualHeight - element.ActualHeight;

    Canvas.SetLeft(element, destinationLeft);
    Canvas.SetTop(element, destinationTop);

    element.ElementContent.Position.X = curContentPoint.X;
    element.ElementContent.Position.Y = curContentPoint.Y;

    e.Handled = true;
}

private Line GetNearestXGridLine(int xpos)
{
    return _gridXLines.OrderBy(gl => Math.Abs((int)gl.X1 - xpos)).First();
}

private Line GetNearestYGridLine(int Ypos)
{
    return _gridYLines.OrderBy(gl => Math.Abs((int)gl.Y1 - Ypos)).First();
}

选择的图形表示 - 现在绘制（最多）3个矩形：从选择的topleft点到相关文本行的最低点，下一行的topleft点到最后一个选定行之前的行的最低点和最后一行的行至点到选择的最低点
获取文字 - 从这些矩形中获取部分文字数据并加入。

如何在wpf c＃中的WritableBitmap中选择或突出显示鼠标移动事件中的文本

1 个答案: