将捕获的ASP.NET异常写入EventLog而不丢失细节

Question

本文详细说明了如何将ASP.NET异常记录到Windows EventLog以及如何向最终用户显示自定义错误页面。

但是，ASP.NET Web应用程序的标准事件日志记录机制自动包含许多本文未显示的有用信息。实施本文中的代码会导致我的错误事件丢失细节/粒度。

例如，使用自动未捕获的异常日志记录，您可以在标题下看到许多属性：事件信息，应用程序信息，进程信息，请求信息，线程信息，自定义事件详细信息。

如何实现对未捕获的异常中记录的所有相同信息的记录，并将我的自定义信息附加到“ 自定义事件详细信息”部分中？最佳答案最好使用某种System.Diagnostics或多种System.Exception或类似的内置方法，即编写尽可能少的代码以编写具有上述所有部分的日志条目，并将任何自定义详细信息附加到字符串中。

如果可能的话，我还想将唯一的散列事件ID（例如b68b3934cbb0427e9497de40663c5225下面的示例）返回给应用程序，以显示在我的ErrorPage.aspx

所需的日志格式示例：

Event code: 3005 
Event message: An unhandled exception has occurred. 
Event time: 15/07/2016 15:44:01 
Event time (UTC): 15/07/2016 14:44:01 
Event ID: b68b3934cbb0427e9497de40663c5225 
Event sequence: 131 
Event occurrence: 2 
Event detail code: 0 

Application information: 
    Application domain: /LM/W3SVC/3/ROOT-1-131130657267252632 
    Trust level: Full 
    Application Virtual Path: / 
    Application Path: C:\WWW\nobulus\nobulusPMM\Application\PMM\ 
    Machine name: L-ADAM 

Process information: 
    Process ID: 47216 
    Process name: iisexpress.exe 
    Account name: L-ADAM\Adam 

Exception information: 
    Exception type: ApplicationException 
    Exception message: Error running stored procedure saveValidation: Procedure or function 'saveValidation' expects parameter '@ValidatedBy', which was not supplied.
   at PMM.Models.PMM_DB.runStoredProcedure(String StoredProcedureName, List`1 SQLParameters) in C:\WWW\nobulus\nobulusPMM\Application\PMM\Models\PMM_DB.cs:line 104
   at PMM.Models.PMM_DB.saveValidation(String PTLUniqueID, String ValidatedBy, DateTime ValidationDateTime, Nullable`1 ValidationCategoryID, String ValidationCategory,     String Comment, Nullable`1 ClockStartDate, Nullable`1 ClockStopDate, String StartRTTStatus, String StopRTTStatus, String LastRTTStatus, Boolean MergedPathway, String     MergedPathwayID, String ExtinctPathwayID, DataTable ChecklistResponses) in C:\WWW\nobulus\nobulusPMM\Application\PMM\Models\PMM_DB.cs:line 265
   at PMM.Validate.lnkSaveButton_Click(Object sender, EventArgs e) in C:\WWW\nobulus\nobulusPMM\Application\PMM\Validate.aspx.cs:line 323
   at System.Web.UI.WebControls.LinkButton.OnClick(EventArgs e)
   at System.Web.UI.WebControls.LinkButton.RaisePostBackEvent(String eventArgument)
   at System.Web.UI.WebControls.LinkButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument)
   at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument)
   at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)
   at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)



Request information: 
    Request URL: http://localhost:6901/Validate?PTLUniqueID=RTT10487 
    Request path: /Validate 
    User host address: ::1 
    User: L-ADAM\Adam 
    Is authenticated: True 
    Authentication Type: Negotiate 
    Thread account name: L-ADAM\Adam 

Thread information: 
    Thread ID: 19 
    Thread account name: L-ADAM\Adam 
    Is impersonating: False 
    Stack trace:    at PMM.Models.PMM_DB.runStoredProcedure(String StoredProcedureName, List`1 SQLParameters) in C:\WWW\nobulus\nobulusPMM\Application\PMM\Models\PMM_DB.    cs:line 104
   at PMM.Models.PMM_DB.saveValidation(String PTLUniqueID, String ValidatedBy, DateTime ValidationDateTime, Nullable`1 ValidationCategoryID, String ValidationCategory,     String Comment, Nullable`1 ClockStartDate, Nullable`1 ClockStopDate, String StartRTTStatus, String StopRTTStatus, String LastRTTStatus, Boolean MergedPathway, String     MergedPathwayID, String ExtinctPathwayID, DataTable ChecklistResponses) in C:\WWW\nobulus\nobulusPMM\Application\PMM\Models\PMM_DB.cs:line 265
   at PMM.Validate.lnkSaveButton_Click(Object sender, EventArgs e) in C:\WWW\nobulus\nobulusPMM\Application\PMM\Validate.aspx.cs:line 323
   at System.Web.UI.WebControls.LinkButton.OnClick(EventArgs e)
   at System.Web.UI.WebControls.LinkButton.RaisePostBackEvent(String eventArgument)
   at System.Web.UI.WebControls.LinkButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument)
   at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument)
   at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)
   at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)


Custom event details: 

Answer 1

更新

我居然发现了使用ILSpy并在不同的框架类漫游ASP.NET内部使用WebErrorEvent，其具有保护的方法来实现相同的行为。

解决方案1：

为此，只需创建一个继承的类WebErrorEvent，然后覆盖其构造函数即可：

public class CustomWebErrorEvent : WebErrorEvent
{
    public CustomWebErrorEvent(string message, EventSource source, int eventCode, Exception ex) : base(message, source, eventCode, ex)
    {
    }
}

然后在Global.asax的错误管理方法中使用它：

protected void Application_Error(Object sender, EventArgs e)
{
    // Log error to the Event Log
    Exception myError = null;
    if (HttpContext.Current.Server.GetLastError() != null)
    {
        var r = new CustomWebErrorEvent("error", null, 120, HttpContext.Current.Server.GetLastError());
    }
}

我很确定也有可能使ASPNET重载以仅直接引发一个自定义WebErrorEvent，但是我还没有找到它。

我仍在尝试找出如何向事件中添加自定义信息的方法，因为Web托管的错误事件不会重写FormatFormatEventEventDetails方法。

解决方案2：

如果不能立即丢失添加自定义字段，则可以使用我编写的类似方法执行相同的输出：

// Log error to the Event Log
Exception myError = null;
if (HttpContext.Current.Server.GetLastError() != null)
{
    var request = HttpContext.Current.Request;
    myError = HttpContext.Current.Server.GetLastError();

    var dateAsBytes = System.Text.Encoding.UTF8.GetBytes(DateTime.Now.ToString("G"));
    var id = Convert.ToBase64String(System.Security.Cryptography.MD5.Create().ComputeHash(dateAsBytes));

    // Event info:
    var eventMessage = myError.Message;
    var currentTime = DateTime.Now.ToString("G");
    var currentTimeUTC = DateTime.UtcNow.ToString("G");

    // Application info:
    var appDomainName = AppDomain.CurrentDomain.FriendlyName;
    var appDomainTrustLevel = (AppDomain.CurrentDomain.IsFullyTrusted) ? "Full" : "Partial";
    var appVirtualPath = VirtualPathUtility.GetDirectory(request.Path);
    var appPath = request.PhysicalApplicationPath;
    var machineName = Environment.MachineName;

    // Process info:
    var process = Process.GetCurrentProcess();
    var processId = process.Id;
    var processName = process.ProcessName;
    var user = System.Security.Principal.WindowsIdentity.GetCurrent().User;
    var accountName = user.Translate(typeof(System.Security.Principal.NTAccount));

    // Exception info:
    var exceptionType = myError.GetType().FullName;
    var exceptionMessage = myError.Message;
    var exceptionStack = myError.StackTrace;

    // Request info:
    var url = request.Url.AbsoluteUri;
    var urlPath = request.Url.PathAndQuery;
    var remoteAddress = request.UserHostAddress;
    var userName = System.Security.Principal.WindowsIdentity.GetCurrent().Name;
    var isAuthenticated = HttpContext.Current.User.Identity.IsAuthenticated;
    var authenticationType = System.Security.Principal.WindowsIdentity.GetCurrent().AuthenticationType;

    // Thread info:
    var impersonationLevel = System.Security.Principal.WindowsIdentity.GetCurrent().ImpersonationLevel;
    var exceptionStack2 = myError.StackTrace;

    // TODO: aggregate all info as string before writting to EventLog.
}

我发现使用现有的.NET Apis几乎可以从您的输出中获取所有必填字段，只是需要知道在将EventEvent输出之前将其汇总为字符串。

您可以看到我正在使用的某些对象（例如AppDomain.CurrentDomain，HttpContext.Current.Request或Process.GetCurrentProcess()返回了很多其他信息，如果需要，也可以将其添加到输出中。

当然，所有这些都可以用一种简化代码的方法来包装。