计算.NET DrawingContext DrawText方法中的文本环绕

Question

我正在开发一个项目,让我近似文本呈现为图像和文本的DHTML编辑器.使用.NET 4 DrawingContext对象的DrawText方法呈现图像.

DrawText方法将文本与字体信息以及尺寸一起使用,并计算使文本尽可能合适所需的包装,如果文本太长则在末尾放置省略号.所以,如果我有以下代码在Rectangle中绘制文本,它将缩写它:

string longText = @"A choice of five engines, although the 2-liter turbo diesel, supposedly good for 48 m.p.g. highway, is not coming to America, at least for now. A 300-horsepower supercharged gasoline engine will likely be the first offered in the United States. All models will use start-stop technology, and fuel consumption will decrease by an average of 19 percent across the A6 lineup. A 245-horsepower A6 hybrid was also unveiled, but no decision has yet been made as to its North America sales prospects. Figure later in 2012, if sufficient demand is detected.";

var drawing = new DrawingGroup();
using (var context = drawing.Open())
{
    var text = new FormattedText(longText,
        CultureInfo.CurrentCulture,
        FlowDirection.LeftToRight,
        new Typeface("Calibri"),
        30,
        Brushes.Green);
    text.MaxTextHeight = myRect.Height;
    text.MaxTextWidth = myRect.Width;

    context.DrawText(text, new Point(0, 0));
}

var db = new DrawingBrush(drawing);
db.Stretch = Stretch.None;
myRect.Fill = db;

有没有办法计算文本的包装方式？在这个例子中,输出的文本包裹在"2升"和"48英里/小时"等,如下图所示:

Answer 1

不确定您是否仍然需要解决方案，或者这个特定的解决方案是否适合您的应用程序，但是如果您在块后面插入以下代码片段，using它将显示每行中的文本（因此文本被破坏以进行换行） 。

我使用非常贫民区/游击队的方法得出了这个解决方案，即在调试时浏览属性，寻找包装的文本段 - 我找到了它们，它们位于可访问的属性中......所以你就可以了。很可能有一种更合适/直接的方法。

// Object heirarchy:
// DrawingGroup (whole thing)
//  - DrawingGroup (lines)
//     - GlyphRunDrawing.GlyphRun.Characters (parts of lines)

// Note, if text is clipped, the ellipsis will be placed in its own 
// separate "line" below.  Give it a try and you'll see what I mean.

List<DrawingGroup> lines = drawing.Children.OfType<DrawingGroup>().ToList();

foreach (DrawingGroup line in lines)
{
    List<char> lineparts = line.Children
        .OfType<GlyphRunDrawing>()
        .SelectMany(grd => grd.GlyphRun.Characters)
        .ToList();

    string lineText = new string(lineparts.ToArray());

    Debug.WriteLine(lineText);
}

顺便说一句，嗨大卫。:-)