把错误信息写入系统日志

在Global.asax 里,我想让程序一有异常就记录错误信息到Windos的事件查看器里.

void Application_Error(object sender, EventArgs e)
    {
         Exception lastError = Server.GetLastError();

         string errMessage = lastError.ToString();

         string logName = "myLog";
         string logMessage= "Url" + Request.Path + "Error:" + errMessage;

 

          if (!EventLog.SourceExists(logName))
         {
             EventLog.CreateEventSource(logName, logMessage);
             EventLog.WriteEntry(logName, logMessage, EventLogEntryType.Information, 1);
             EventLog.WriteEntry(logName, logMessage, EventLogEntryType.Error, 2);
             EventLog.WriteEntry(logName, logMessage, EventLogEntryType.Warning, 3);
             EventLog.WriteEntry(logName, logMessage, EventLogEntryType.SuccessAudit, 4);
             EventLog.WriteEntry(logName, logMessage, EventLogEntryType.FailureAudit, 5);       

          }

}

 

我引发了异常,可我在Windos的事件查看器里没发现有我的错误日志.

哪里错了呢?