5

我遇到了 C# 程序中 WebBrowsing 自动化的问题。我之前使用过 BHO 的代码,它在那里工作。但是在纯 c# 程序中似乎存在某种死锁。我已经指示我的程序单击搜索按钮,然后等待(通过手动重置事件)让 documentcomplete 发出信号。但是现在似乎直到 ManualResetEvent 发出超时信号才处理对搜索按钮的单击。此后,单击并触发 DocumentComplete-Event。

对于该程序的结构: WebBrowser-Control 是 WindowsForm 的一部分。WebBrowser 控件被传递给运行线程的类。该类再次将控制权传递给另一个类,在该类中根据加载的网络浏览器对具体行为进行编程。

所以在代码中是这样的:

  1. 线程的设置

    _runner = new Thread(runner);
    _runner.SetApartmentState(ApartmentState.STA);
    _runner.IsBackground = true;
    _runner.Start();
    
  2. Runner-Method的处理

    b.placeTipp(workStructure);
    
  3. PlaceTipp 方法

    public void placeTipp(ref OverallTippStructure tipp)
        {
            _expectedUrl = String.Empty;
            _betUrl = String.Empty;
            _status = BookieStatusType.CHECKLOGIN;
    
            while (true)
            {
                _mreWaitForAction.Reset();
                checkIETab();
    
                switch (_status)
                {
                    case BookieStatusType.REQUESTWEBSITE:
                        ConsoleWriter.writeToConsole(String.Format("Bookie {0}: Keine IE-Tab vorhanden. Fordere eine an", this.BookieName));
                        //if (RequestIETabEvent != null)
                        //    RequestIETabEvent(this, new EventArgs());
                        _status = BookieStatusType.NAVIGATETOWEBSITE;
                        _mreWaitForAction.Set();
                        break;
                    case BookieStatusType.NAVIGATETOWEBSITE:                                                
                        _webBrowser.Navigate(@"http://www.nordicbet.com");
                        break;
                    case BookieStatusType.CHECKLOGIN:
                        checkLogin();
                        break;
                    case BookieStatusType.LOGINNEEDED:
                        doLogin();
                        break;
                    case BookieStatusType.LOGGEDIN:
                        _status = BookieStatusType.SEARCHTIPP;
                        _mreWaitForAction.Set();
                        break;
                    case BookieStatusType.SEARCHTIPP:
                        searchTipp(tipp);
                        break;
                    case BookieStatusType.NAVTOSB:
                        NavToSB();
                        break;
                    case BookieStatusType.GETMARKET:
                        getMarket(tipp);
                        break;
                    case BookieStatusType.PLACEBET:
                        placeBet(tipp);
                        break;
                    case BookieStatusType.CONFIRMBET:
                        confirmBet();
                        break;
                    case BookieStatusType.EXTRACTBETDATA:
                        extractBetId(ref tipp);
                        break;
                    case BookieStatusType.FINISHED:
                        return;
                }
    
    
                if (!_mreWaitForAction.WaitOne(60000))
                {
                    //Sonderüberpüfung be LoginNeeded
                    if (_status == BookieStatusType.LOGINNEEDED)
                    {
                        //checkLogin();
                        throw new BookieLoginFailedExcpetion();
                    }
                    //TIMEOUT!
                    ConsoleWriter.writeToConsole(String.Format("Bookie {0}: Timeout bei warten auf nächsten Schritt. Status war {1}", this.BookieName, this._status.ToString()));
                    throw new BookieTimeoutExcpetion(String.Format("Bookie {0}: Timeout bei dem Warten auf Ereignis", this.BookieName));
                }
            }
        }
    
  4. 发生死锁的 SearchTipp-Method:

    private void searchTipp(OverallTippStructure tipp)
        {
            if (_webBrowser.InvokeRequired)
            {
                _webBrowser.Invoke(new delegatePlaceBet(searchTipp), new object[] { tipp });
            }
            else
            {
                ConsoleWriter.writeToConsole(String.Format("Bookie {0}: Suche Tipp {1}", this.BookieName, tipp.BookieMatchName));
                _expectedUrl = String.Empty;
                if (!_webBrowser.Url.ToString().StartsWith("https://www.nordicbet.com/eng/sportsbook"))
                {
                    ConsoleWriter.writeToConsole(String.Format("Bookie {0}: Nicht auf Sportsbookseite. Navigiere", this.BookieName));
                    _status = BookieStatusType.NAVTOSB;
                    _mreWaitForAction.Set();
                    return;
                }
                _searchCompleted = false;
                HtmlDocument doc = _webBrowser.Document;
    
                if (doc != null)
                {
    
                    mshtml.IHTMLInputElement elemSearch = (mshtml.IHTMLInputElement)doc.GetElementById("query").DomElement;
                    if (elemSearch != null)
                    {
                        Thread.Sleep(Delayer.delay(2000, 10000));
                        elemSearch.value = tipp.BookieMatchName;
    
                        mshtml.IHTMLElement elemSearchButton = (mshtml.IHTMLElement)doc.GetElementById("search_button").DomElement;
                        if (elemSearchButton != null)
                        {
                            Thread.Sleep(Delayer.delay(900, 4000));
    
                            elemSearchButton.click();
                            //elemSearchButton.InvokeMember("click");
    
                            if (!_mreWaitForAction.WaitOne(10000)) //Here The Deadlock happens
                            {
                                //Now the click event and therefor the search will be executed
                                ConsoleWriter.writeToConsole(String.Format("Bookie {0}: Suche ist auf Timeout gelaufen", this.BookieName));
                                throw new BookieTimeoutExcpetion(String.Format("Bookie {0}: Suche ist auf Timeout gelaufen", this.BookieName));
                            }                                                        
    
                            _mreWaitForAction.Reset();
                            HtmlElement spanResult = doc.GetElementById("total_ocs_count");
                            while (spanResult == null)
                            {
                                Thread.Sleep(500);
                                spanResult = doc.GetElementById("total_ocs_count");
                            }
    
                            int total_ocs_count = 0;
                            if (!Int32.TryParse(spanResult.InnerHtml, out total_ocs_count))
                            {
                                ConsoleWriter.writeToConsole(String.Format("Bookie {0}: Tip {1} nicht gefunden", this.BookieName, tipp.BookieMatchName));
                                throw new BookieTippNotFoundExcpetion(String.Format("Bookie {0}: Tip {1} nicht gefunden", this.BookieName, tipp.BookieMatchName));
                            }
    
                            if (total_ocs_count <= 0)
                            {
                                ConsoleWriter.writeToConsole(String.Format("Bookie {0}: Tip {1} nicht gefunden", this.BookieName, tipp.BookieMatchName));
                                throw new BookieTippNotFoundExcpetion(String.Format("Bookie {0}: Tip {1} nicht gefunden", this.BookieName, tipp.BookieMatchName));
                            }
                            /*
                        else if (total_ocs_count > 1)
                        {
                            throw new BookieMoreThanOneFoundExcpetion(String.Format("Bookie {0}: Tipp {1} nicht eindeutig", this.BookieName, tipp.BookieMatchName));
                        }
                        */
                            ConsoleWriter.writeToConsole(String.Format("Bookie {0}: Tip {1} gefunden", this.BookieName, tipp.BookieMatchName));
                            _status = BookieStatusType.GETMARKET;
                        }
                    }
                }
                _mreWaitForAction.Set();
            }
        }
    

有人知道这里发生了什么吗?

谢谢

光之使者

4

1 回答 1

3

通过这样做_webBrowser.Invoke(new delegatePlaceBet(searchTipp), new object[] { tipp }),您可以使该searchTipp方法在主 UI 线程上同步执行。WebBrowser这是可以理解的,因为除了创建控件的原始线程之外,您无法从任何线程访问API。

但是,这样做_mreWaitForAction.WaitOne(10000)会在主 UI 线程上执行过多的调用,从而有效地阻塞消息循环(由 启动Application.Run)。WebBrowser需要一个功能性的消息循环,它不断地发送 Windows 消息,否则DocumentCompleted不会被触发,你就会陷入死锁。

我的理解是,你在这里只创建另一个线程来组织你的自动化场景的工作流程。你真的不需要另一个线程。 这是一个如何在主 UI 线程上异步完成的示例,使用async/ await这是一个WebBrowser在控制台应用程序中使用的示例。

或者,作为一种解决方法,您可以WaitWithDoEvents此处使用,如下所示_mreWaitForAction.WaitWithDoEvents(10000):它等待句柄,同时仍在发送消息。您应该意识到使用Application.DoEvents().

请注意,如果您使用嵌套消息循环,您仍然不需要单独的线程。它将为您提供主 UI 线程上的线性代码工作流。例子:

private void buttonStart_Click(object sender, EventArgs e)
{
    using (var mre = new ManualResetEvent(false))
    {
        WebBrowserDocumentCompletedEventHandler handler = (s, args) => 
            mre.Set();
        this.webBrowser.DocumentCompleted += handler;
        try
        {
            this.webBrowser.Navigate("http://www.example.com");
            mre.WaitWithDoEvents(10000);
        }
        finally
        {
            this.webBrowser.DocumentCompleted -= handler;
        }
    }
    MessageBox.Show(this.webBrowser.Document.Body.OuterHtml);
}

尽管正如我上面提到的,您可以更自然地实现相同的目标,并且无需嵌套消息循环,使用async/ await,这是执行此操作的首选方式,IMO。

于 2013-12-09T01:35:37.013 回答