处理XPS文档时出现“无法识别URI前缀”

Question

我有一个简单的程序，可以读取XPS文件并创建重复的页面。

原始文档：

获得5页的输出：

如您所见，操作非常简单。但是我发现，如果创建的页面过多，则会抛出异常“ System.NotSupportedException。无法识别URI前缀”。。

我创建了一个测试程序，该程序增加了while循环中的页面数量，如您所见，我将打印用于存储xps文件的每个临时内存流的URI（仅用于检查冲突或进行调试）我发现每次计数器达到 11 时，都会在此处引发异常。

翻译：System.NotSupportedException。无法识别URI前缀
有趣的是，这个问题是可重复的，我对发生的事情一无所知：\任何建议将不胜感激，谢谢！

class Program
{
    [STAThread]
    static void Main(string[] args)
    {
        var xpsFile = File.ReadAllBytes(@"Test.xps");
        Stopwatch sw1 = new Stopwatch();
        int i = 5;
        while (true)
        {
            sw1.Start();

            var output = createDuplicatePages(xpsFile, i++);
            sw1.Stop();

            File.WriteAllBytes(@"output.xps", output);
            Console.WriteLine($"Trial {i} Completed. {sw1.ElapsedMilliseconds}");
            Console.ReadLine();
        }

    }

    static byte[] createDuplicatePages(byte[] originalXPS, int numberOfCopies)
    {

        byte[] ret = originalXPS;
        try
        {
            using (MemoryStream outputStream = new MemoryStream())
            {
                Package container = Package.Open(outputStream, FileMode.Create);
                XpsDocument xpsDoc = new XpsDocument(container);
                XpsDocumentWriter writer = XpsDocument.CreateXpsDocumentWriter(xpsDoc);
                SerializerWriterCollator vxpsd = writer.CreateVisualsCollator();
                vxpsd.BeginBatchWrite();
                for (int nthCopy = 0; nthCopy < numberOfCopies; nthCopy++)
                {
                    MemoryStream inputStream = new MemoryStream(originalXPS);
                    string memoryStreamUri = "memorystream://" + Path.GetFileName(Guid.NewGuid().ToString() + ".xps");
                    Uri packageUri = new Uri(memoryStreamUri);
                    Console.WriteLine(packageUri.AbsoluteUri);
                    Package oldPackage = Package.Open(inputStream);
                    PackageStore.AddPackage(packageUri, oldPackage);
                    using (XpsDocument xpsOld = new XpsDocument(oldPackage, CompressionOption.Normal, memoryStreamUri))
                    {
                        FixedDocumentSequence seqOld = xpsOld.GetFixedDocumentSequence();                          
                        foreach (DocumentReference r in seqOld.References)
                        {
                            FixedDocument d = r.GetDocument(false);

                            foreach (PageContent pc in d.Pages)
                            {
                                FixedPage fixedPage = pc.GetPageRoot(false);
                                double width = fixedPage.Width;
                                double height = fixedPage.Height;

                                System.Windows.Size sz = new System.Windows.Size(width, height);
                                fixedPage.Width = width;
                                fixedPage.Height = height;
                                fixedPage.Measure(sz);
                                fixedPage.Arrange(new System.Windows.Rect(new System.Windows.Point(), sz));

                                ContainerVisual newPage = new ContainerVisual();

                                newPage.Children.Add(fixedPage);

                                vxpsd.Write(newPage);

                            }
                        }
                        PackageStore.RemovePackage(packageUri);
                    }
                    oldPackage.Close();
                }
                vxpsd.EndBatchWrite();
                container.Close();
                ret = outputStream.ToArray();
            }             
            return ret;
        }
        catch (Exception e)
        {
            return originalXPS;
        }
    }
}

Test.xps：
https://drive.google.com/file/d/1kXrcKeDgAeSsIGqQwx-UpRhLdx8eW0PV/view?usp=sharing

------ 10/9/2018更新-----

我偶然发现以下修改确实解决了问题，但是为什么呢？不知道：\

vxpsd.BeginBatchWrite();
for (int nthCopy = 0; nthCopy < numberOfCopies; nthCopy++)
{
     MemoryStream inputStream = new MemoryStream(originalXPS);
     string memoryStreamUri = "memorystream://" + Path.GetFileName(Guid.NewGuid().ToString() + ".xps");

收件人

vxpsd.BeginBatchWrite();
string memoryStreamUri = "memorystream://" + Path.GetFileName(Guid.NewGuid().ToString() + ".xps");
for (int nthCopy = 0; nthCopy < numberOfCopies; nthCopy++)
{
     MemoryStream inputStream = new MemoryStream(originalXPS);