c# - 在 BackgroundWorker 线程上创建 FlowDocument

Question

我需要从大量数据中动态生成 FlowDocument。因为这个过程需要几分钟，所以我想在后台线程上执行操作而不是让 UI 挂起。

但是，我无法在非 UI 线程上生成 FlowDocument，否则尝试插入矩形和图像会导致运行时错误，提示它不是 STA 线程。

StackOverflow 上有几个线程似乎涉及我遇到的相同问题:

• Accessing a WPF FlowDocument in a BackGround Process

• WPF : Is it impossible to UI load in background thread?

在第一个链接中有人建议如下:

"What I'd do: use a XamlWriter and serialize the FlowDocument into an XDocument. The serialization task involves the Dispatcher, but once it's done, you can run as many wacky parallel analyses of the data as you want and nothing in the UI will affect it. (Also once it's an XDocument you query it with XPath, which is a pretty good hammer, so long as your problems are actually nails.)"

有人可以详细说明作者的意思吗？

Answer 1

对于任何 future 的访客由于这篇文章，我遇到了同样的问题并解决了所有问题 article

最后做的是在后台线程上创建对象

            Thread loadingThread = new Thread(() =>
        {
            //Load the data
            var documant = LoadReport(ReportTypes.LoadOffer, model, pageWidth);

            MemoryStream stream = new MemoryStream();
            //Write the object in the memory stream
            XamlWriter.Save(documant, stream);
            //Move to the UI thread
            Dispatcher.BeginInvoke(
               DispatcherPriority.Normal,
               (Action<MemoryStream>)FinishedGenerating,
               stream);
        });

        // set the apartment state  
        loadingThread.SetApartmentState(ApartmentState.STA);

        // make the thread a background thread  
        loadingThread.IsBackground = true;

        // start the thread  
        loadingThread.Start();

然后将结果作为 xaml 写入内存流，以便我们可以在主线程中读取它

void FinishedGenerating(MemoryStream stream)
    {
        //Read the data from the memory steam
        stream.Seek(0, SeekOrigin.Begin);
        FlowDocument result = (FlowDocument)XamlReader.Load(stream);

        FlowDocumentScrollViewer = new FlowDocumentScrollViewer
        {
            Document = result
        };
    //your code...

希望它能为其他人节省一些时间:)