主线程上单独的线程引发事件中的 C# .NET Web 浏览器控件

我需要在paralel中抓取很多页面，而我的UI线程不能被阻止。我正在为每个页面（url）创建线程，并在该线程中实例化webBrowser控件以执行javascript并在此之后获取html。当 webBrowser 获取 html 时，我在 UI 线程上引发事件以注册浏览器已完成其工作，因为我想知道所有浏览器何时都获取了 html，以便我可以合并所有数据并显示它。

1.）第一个探测是，有些线程永远不会引发事件，所以我一直在等待。

2.）第二个问题是我无法在不导致外部浏览器触发的情况下处理浏览器，一直拉着浏览器下方的地毯，所以他决定通过在用户默认浏览器中打开页面来继续我猜。但如果根本不处理，我的公羊就用完了。

我一直在搜索，找到了很多相关的东西，但我未能为我的用例实现它。这是我的代码：

 [System.Runtime.InteropServices.ComVisibleAttribute(true)]
    public partial class Form1 : Form
    {
        public delegate void ThreadFinishedEventHandler(object source, EventArgs e);
        public event ThreadFinishedEventHandler threadFinishedEvent;
        int threadCount = 0;
        int threadReturnedCount = 0;
        List<string> linksGlobal;
        public Form1()
        {
            InitializeComponent();
            threadFinishedEvent += new ThreadFinishedEventHandler(OnThreadFinished); 
        }
        private void Form1_Load(object sender, EventArgs e)
        {
        }
        private void btnGO_Click(object sender, EventArgs e)
        {
            scrapeLinksWithBrowsersInSeparateThreads();
        }

        private void scrapeLinksWithBrowsersInSeparateThreads()
        {
            linksGlobal = getLinks(); //10 urls all the same -> https://sports.betway.com
            threadCount = linksGlobal.Count;
            Random rand = new Random(123);
            int waitTime = 0;//trying not to be registered as DOS attack or smth
            foreach (string url in linksGlobal)
            {
                runBrowserThread(url, waitTime);
                waitTime += rand.Next(500, 3000) + 500;//each browser will start navigating withing 1 - 4 seconds interval from each other
            }
        }

        public void runBrowserThread(string url, int waitTime)
        {
            var th = new Thread(() =>
            {
                try
                {
                    WebBrowserDocumentCompletedEventHandler completed = null;
                    WebBrowser wb = new WebBrowser();
                    completed = (sndr, e) =>
                    {
                        if (e.Url.AbsolutePath != (sndr as WebBrowser).Url.AbsolutePath)
                        {
                            wb.DocumentCompleted -= completed;
                            string html = (sndr as WebBrowser).Document.Body.InnerHtml;
                            threadFinishedEvent.Raise(this, EventArgs.Empty); // I have EventExtension allowing me this
                            //wb.Dispose(); //whenever and wherever I put this it causes external browser to fire
                            // Application.ExitThread();  //this sometimes seems to cause event never firing, not shure
                        }
                    };
                    wb.DocumentCompleted += completed;
                    wb.ScriptErrorsSuppressed = true;
                    Thread.Sleep(waitTime); //tryin not to get registerd as DOS attck or smth, each browser will start navigating withing 1 - 4 seconds interval from each other
                    wb.Navigate(url);
                    Application.Run();
                }
                catch (Exception ex)
                {
                    throw ex;
                }
            });
            th.SetApartmentState(ApartmentState.STA);
            th.Start();
        }

        private void OnThreadFinished(object source, EventArgs e)
        {
            threadReturnedCount++; // i get this for smth like 3 - 5 out od 11 threads, then this event stops being raised, dunno why
            if (threadReturnedCount == threadCount)
            {
                // Do work
                //this never happens cos a lot of threads never raise event, some do
            }
        }

        private List<string> getLinks()
        {
            List<string> links = new List<string>();
            links.Add("https://sports.betway.com");
            links.Add("https://sports.betway.com");
            links.Add("https://sports.betway.com");
            links.Add("https://sports.betway.com");
            links.Add("https://sports.betway.com");
            links.Add("https://sports.betway.com");
            links.Add("https://sports.betway.com");
            links.Add("https://sports.betway.com");
            links.Add("https://sports.betway.com");
            links.Add("https://sports.betway.com");
            links.Add("https://sports.betway.com");
            return links;
        }
      }

附言从线程返回数据是单独的问题，我还没有实现它，但首先我想解决这个问题。我将使用对象工厂，它将像Factory.createObject（html）一样从每个线程调用，我将不得不在该工厂上使用某种锁定，因为它将位于主线程上。