我在C#-Program中遇到了WebBrowsing自动化的问题.
我之前使用过代码来获取BHO,并且它正在运行.
但在纯粹的c#程序中,似乎存在某种僵局.我已经指示我的程序点击搜索按钮,然后等待(通过手动重新发送)文档完成信号.但是现在似乎在ManualResetEvent发出超时信号之前不会处理点击搜索按钮.然后单击,并且还会触发DocumentComplete-Event.
我之前使用过代码来获取BHO,并且它正在运行.
但在纯粹的c#程序中,似乎存在某种僵局.我已经指示我的程序点击搜索按钮,然后等待(通过手动重新发送)文档完成信号.但是现在似乎在ManualResetEvent发出超时信号之前不会处理点击搜索按钮.然后单击,并且还会触发DocumentComplete-Event.
对于该程序的结构：
WebBrowser-Control是WindowsForm的一部分. WebBrowser控件传递给运行Thread的Class.该类再次将控件传递给另一个类,其中根据加载的webbrowser编程具体行为.
所以在Code中这样看起来：
>线程的设置
_runner = new Thread(runner); _runner.SetApartmentState(ApartmentState.STA); _runner.IsBackground = true; _runner.Start();
>使用跑步者方法的处理
b.placeTipp(workStructure);
> 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));
}
}
}
>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}",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",tipp.BookieMatchName));
throw new BookieTippNotFoundExcpetion(String.Format("Bookie {0}: Tip {1} nicht gefunden",tipp.BookieMatchName));
}
if (total_ocs_count <= 0)
{
ConsoleWriter.writeToConsole(String.Format("Bookie {0}: Tip {1} nicht gefunden",tipp.BookieMatchName));
}
/*
else if (total_ocs_count > 1)
{
throw new BookieMoreThanOneFoundExcpetion(String.Format("Bookie {0}: Tipp {1} nicht eindeutig",tipp.BookieMatchName));
}
*/
ConsoleWriter.writeToConsole(String.Format("Bookie {0}: Tip {1} gefunden",tipp.BookieMatchName));
_status = BookieStatusType.GETMARKET;
}
}
}
_mreWaitForAction.Set();
}
}
有人知道这里发生了什么？
谢谢
lichtbringer
解决方法
通过执行_webBrowser.Invoke(new delegatePlaceBet(searchTipp),new object [] {tipp}),可以在主UI线程上同步执行searchTipp方法.这是可以理解的,因为您无法从创建控件的原始线程以外的任何线程访问WebBrowser API.
但是,通过这样做,_mreWaitForAction.WaitOne(10000)调用将在主UI线程上执行,从而有效地阻止消息循环(由Application.Run启动). WebBrowser需要一个功能性的消息循环,它不断地传递Windows消息,否则DocumentCompleted不会被触发,并且您将陷入僵局.
我的理解是,您只需在此处创建另一个线程来组织自动化方案的工作流程.你真的不需要另一个线程. Here’s an example如何在主UI线程上异步完成,使用async / await和here’s an example在控制台应用程序中使用WebBrowser.
或者,作为一种变通方法,您可以使用here中的WaitWithDoEvents,如下所示：_mreWaitForAction.WaitWithDoEvents(10000).它在等待处理消息时等待处理.您应该了解使用Application.DoEvents()创建嵌套消息循环的potential implications.
注意,如果使用嵌套消息循环,则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程.例：
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);
}
虽然正如我上面提到的,你可以更自然地实现同样的目的,没有嵌套的消息循环,使用async / await,这是这样做的首选方法,IMO.
