Question

我需要跟踪C＃应用程序中的USB插入和删除事件，以便根据SO上的其他问题提出以下想法。

我无法使用此方法

var drives = DriveInfo.GetDrives()
    .Where(drive => drive.IsReady && drive.DriveType == DriveType.Removable).ToList();

因为当您需要区分已连接和已断开连接的设备时，它会导致很多麻烦（新设备可能具有相同的驱动器号和名称，就像之前缓存的设备一样）。

所以我决定使用WMI来解决这个问题，但我发现通过Win32_USBHub类获取指定USB设备的驱动器号是不可能的。然后我想我可以像这样执行另一个查询

foreach (ManagementObject device in new ManagementObjectSearcher(@"SELECT * FROM Win32_USBHub").Get())
{
    string deviceID = (string)device.GetPropertyValue("DeviceID");

    Console.WriteLine("{0}", deviceID);

    string query = string.Format("SELECT * FROM Win32_LogicalDisk WHERE DeviceID='{0}'", deviceID);
    foreach (ManagementObject o in new ManagementObjectSearcher(query).Get())
    {
        string name = (string)o.GetPropertyValue("Name");
        Console.WriteLine("{0}", name);
    }

    Console.WriteLine("==================================");
}

但它根本不起作用 - 我得到一个例外＆＃34;无效的查询＆＃34;每当我尝试执行与Win32_LogicalDisk表一起使用的查询时。

为什么呢？我究竟做错了什么？我该如何解决？也许有更好的方法来解决这个问题？

提前致谢。

Answer 1

你得到并且异常，因为你的deviceID包含需要转义的字符（反斜杠）。通过简单的替换，你不应该得到例外。

string query = string.Format("SELECT * FROM Win32_LogicalDisk WHERE DeviceID='{0}'", deviceID.Replace(@"\", @"\\"));

然而，从WMI获取USB驱动器号有点复杂。你需要经历一些课程，如@MSalters在评论中发布的链接中所述：Win32_DiskDrive-> Win32_DiskDriveToDiskPartition -> Win32_DiskPartition -> Win32_LogicalDiskToPartition -> Win32_LogicalDisk.

发现here的一些修改后的代码对我有用：

foreach (ManagementObject device in new ManagementObjectSearcher(@"SELECT * FROM Win32_DiskDrive WHERE InterfaceType LIKE 'USB%'").Get())
{
    Console.WriteLine((string)device.GetPropertyValue("DeviceID"));
    Console.WriteLine((string)device.GetPropertyValue("PNPDeviceID"));                

    foreach (ManagementObject partition in new ManagementObjectSearcher(
        "ASSOCIATORS OF {Win32_DiskDrive.DeviceID='" + device.Properties["DeviceID"].Value
        + "'} WHERE AssocClass = Win32_DiskDriveToDiskPartition").Get())
    {
        foreach (ManagementObject disk in new ManagementObjectSearcher(
                    "ASSOCIATORS OF {Win32_DiskPartition.DeviceID='"
                        + partition["DeviceID"]
                        + "'} WHERE AssocClass = Win32_LogicalDiskToPartition").Get())
        {
            Console.WriteLine("Drive letter " + disk["Name"]);
        }
    }
}

Answer 2

这是michalk对C＃8的答案的重构版本。

我将其与Detecting USB drive insertion and removal using windows service and c#相关问题的答案结合使用

        static IEnumerable<(string deviceId, string pnpDeviceId, string driveLetter)> SelectDeviceInformation()
        {
            foreach (ManagementObject device in SelectDevices())
            {
                var deviceId = (string)device.GetPropertyValue("DeviceID");
                var pnpDeviceId = (string)device.GetPropertyValue("PNPDeviceID");
                var driveLetter = (string)SelectPartitions(device).SelectMany(SelectDisks).Select(disk => disk["Name"]).Single();

                yield return (deviceId, pnpDeviceId, driveLetter);
            }

            static IEnumerable<ManagementObject> SelectDevices() => new ManagementObjectSearcher(
                    @"SELECT * FROM Win32_DiskDrive WHERE InterfaceType LIKE 'USB%'").Get()
                .Cast<ManagementObject>();

            static IEnumerable<ManagementObject> SelectPartitions(ManagementObject device) => new ManagementObjectSearcher(
                    "ASSOCIATORS OF {Win32_DiskDrive.DeviceID=" +
                    "'" + device.Properties["DeviceID"].Value + "'} " +
                    "WHERE AssocClass = Win32_DiskDriveToDiskPartition").Get()
                .Cast<ManagementObject>();

            static IEnumerable<ManagementObject> SelectDisks(ManagementObject partition) => new ManagementObjectSearcher(
                    "ASSOCIATORS OF {Win32_DiskPartition.DeviceID=" +
                    "'" + partition["DeviceID"] + "'" +
                    "} WHERE AssocClass = Win32_LogicalDiskToPartition").Get()
                .Cast<ManagementObject>();
        }

如何使用WMI

2 个答案: