c# - WPF 如何将 FlowDocument BGImage 转换为 FixedDocument 并在 DocumentViewer 中显示？

Question

我有一个带有背景图像的 FlowDocument。目前它不能在 FlowDocumentReader 中正确显示，因为当文档上下滚动时背景图像保持居中。如何将这个FlowDocument转为FixedDocument，在DocumentViewer中显示，背景图也固定了？

我使用来自 here 的转换逻辑.但它不显示 FlowDocument.Background 图像。

    private FixedDocument convert(FlowDocument flowDocument)
    {
        if (flowDocument == null)
            return null;
        var paginator = ((IDocumentPaginatorSource)flowDocument).DocumentPaginator;
        var package = Package.Open(new MemoryStream(), FileMode.Create, FileAccess.ReadWrite);
        var packUri = new Uri("pack://temp.xps");
        PackageStore.RemovePackage(packUri);
        PackageStore.AddPackage(packUri, package);
        var xps = new XpsDocument(package, CompressionOption.NotCompressed, packUri.ToString());
        XpsDocument.CreateXpsDocumentWriter(xps).Write(paginator);
        FixedDocument doc = xps.GetFixedDocumentSequence().References[0].GetDocument(true);
        return doc;
    }

Answer 1

你写的

I have a FlowDocument with Background image. Currently it does not display properly in FlowDocumentReader since the background image stays centered when document is scrolled up and down.

不完全是您特定问题的答案，但要避免这种情况，请设置 ImageBrush.ViewportUnits至 BrushMappingMode.Absolute .然后，设置 ImageBrush.Viewport到您的背景图像的所需尺寸:

        <FlowDocumentReader ViewingMode="Scroll">
            <FlowDocument>
               <FlowDocument.Background>
                    <ImageBrush TileMode="Tile" Stretch="Fill" Viewport="0,0,1000,400" ViewportUnits="Absolute">
                        <ImageBrush.ImageSource>
                            <!--Image source here...-->
                        </ImageBrush.ImageSource>
                    </ImageBrush>

可选择设置ImageBrush.Stretch至 Stretch.Fill用你的图像填充你指定的视口(viewport)，并设置ImageBrush.TileMode至 TileMode.Tile使背景图像重复。