C# 4.0 启动ManagementEventWatcher时未发现异常

启动MaagementEventWatcher时，有时未发现异常

我的代码示例如下所示：

 try
        {
            string scopePath = @"\\.\root\default";
            ManagementScope managementScope = new ManagementScope(scopePath);
            WqlEventQuery query =
                new WqlEventQuery(
                    "SELECT * FROM RegistryKeyChangeEvent WHERE " + "Hive = 'HKEY_LOCAL_MACHINE'"
                    + @"AND KeyPath = 'HARDWARE\\DEVICEMAP\\SERIALCOMM'");
            registryWatcher = new ManagementEventWatcher(managementScope, query);
            registryWatcher.EventArrived += new EventArrivedEventHandler(SerialCommRegistryUpdated);

            registryWatcher.Start();
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
            if (registryWatcher != null)
            {
                registryWatcher.Stop();
            }
        }

例外情况：

  Not found
  at System.Management.ManagementException.ThrowWithExtendedInfo(ManagementStatus errorCode)
  at System.Management.ManagementEventWatcher.Start()
  at MTTS.LabX.RockLog.AppService.USBMonitor.AddRegistryWatcherHandler()]

---

注意：我在注册表中进行了检查，找到了文件夹和文件。

当WQL查询中没有匹配项时，将引发ManagementException“Not found”。可能您指定了错误的密钥路径，或者密钥路径不再可用

事实上，问题是，在笔记本电脑（具有串行端口的PC机）中，在启动首次SERIALCOMM文件夹时没有在注册表中创建，因为

基本上，我们将设备插入SERIALCOMM文件夹将创建的USB端口或串行端口，在这种情况下，我们使用WMI从注册表获取连接的通信端口

在某些笔记本电脑中，没有连接USB端口和串行端口，因此未创建SERIALCOMM文件夹，在访问此注册表路径时，我们会收到错误

所以解决办法是,

try
            {
                string scopePath = @"\\.\root\default";
                ManagementScope managementScope = new ManagementScope(scopePath);

                string subkey = "HARDWARE\\DEVICEMAP\\SERIALCOMM";

                using (RegistryKey prodx = Registry.LocalMachine)
                {
                    prodx.CreateSubKey(subkey);
                }

                WqlEventQuery query = new WqlEventQuery(
                    "SELECT * FROM RegistryKeyChangeEvent WHERE " +
                   "Hive = 'HKEY_LOCAL_MACHINE'" +
                  @"AND KeyPath = 'HARDWARE\\DEVICEMAP\\SERIALCOMM'");

                registryWatcher = new ManagementEventWatcher(managementScope, query);

                registryWatcher.EventArrived += new EventArrivedEventHandler(SerialCommRegistryUpdated);
                registryWatcher.Start();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
                if (registryWatcher != null)
                {
                    registryWatcher.Stop();
                }
            }

---

我在注册表中检查了路径或文件夹（也有项）是否可用。是的，我在事件日志事件筛选器中得到了此错误，查询“SELECT*FROM\uuuu InstanceModificationEvent WITHIN 60 WHERE TargetInstance ISA”Win32\u处理器由于错误0x80041003，无法在命名空间“///root/CIMV2”中重新激活“AND TargetInstance.LoadPercentage>99”。在更正问题之前，无法通过此筛选器传递事件。