获取当前 USB 电源状态
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【中文标题】获取当前 USB 电源状态【英文标题】：Getting current USB power state 【发布时间】：2018-08-07 11:26:20 【问题描述】：我一直在尝试读取 USB 端口 (D0/D1/D2/D3) 的当前电源状态。我无法找到有关如何访问实际状态的太多信息。这是USB Device Power States on Microsoft docs 的描述。它有一整节关于更改，但真的不知道如何阅读它。我在 Windows 和硬件级别上工作的经验很少，如果很明显，请原谅。
我还发现了这个用 C 语言编写的 Microsoft 调试应用程序，名为 USBView。如果您安装它并打开 USB 树，则为各个端口显示的第一个信息是其电源状态。
例如
Device Power State: PowerDeviceD2
它有 source available on GitHub，但文件超过 5000 行长，我无法很好地导航 C 代码以告诉如何实际读取电源状态。
我正在尝试将它实现到 C# 应用程序中，但我们将不胜感激任何语言的帮助！
【问题讨论】：
花 2 分钟找出答案。它在Enum.c 文件中，该方法称为AcquireDevicePowerState，它从注册表中读取一个值
@Franck 我仍然无法弄清楚所需数据的来源..
您无法读取文件？字面上有 2 行代码，一个从注册表读取，一个有一个开关来返回一个或另一个值。它使用SetupDiGetDeviceRegistryProperty 一个普通的API 方法和here's the help on it 从注册表中读取。只需传递正确的参数，您就可以开始了。
【参考方案1】：
在对 USBView 源代码进行了大量挖掘之后，我发现您需要执行以下操作：
使用获取设备信息集的句柄
IntPtr deviceInfoSet = SetupDiGetClassDevs(ref classGuid, null, IntPtr.Zero, 0x00000002 | 0x00000010)
USB 设备的classGuid 是"A5DCBF10-6530-11D2-901F-00C04FB951ED"
使用获取单个设备信息
SetupDiEnumDeviceInfo(deviceInfoSet, index, ref deviceInfoData)
其中deviceInfoData 是SP_DEVINFO_DATA 结构的一个实例，其值cbSize inicializace 为28。（然后设备信息将存储在此结构中。）
您从 index = 0 开始，然后递增直到方法返回 false 和 Marshal.GetLastWin32Error() 返回 259 (ERROR_NO_MORE_ITEMS) 以获取所有设备。
然后您使用SetupDiGetDeviceRegistryProperty 检索电源属性。
您可以：
A.传入CM_POWER_DATA（那么你应该将DllImport方法签名中的byte[]替换为ref CM_POWER_DATA）
B.传入一个字节数组，然后将字节数组解析为CM_POWER_DATA（来自this answer 的代码证明非常擅长）。
这里我展示了选项 B - 传入字节数组。功率数据将在data 变量中。 （已跳过转换。）
//sizeof evaluates to 56, if you want to hardcode it
byte[] data = new byte[Marshal.SizeOf<CM_POWER_DATA>()];
SetupDiGetDeviceRegistryProperty(
deviceInfoSet,
ref deviceInfoData,
0x0000001E, //the property SPDRP_DEVICE_POWER_DATA
out uint type,
data,
data.Length,
out uint size)
);
然后您可以使用 SetupDiGetDeviceRegistryProperty 函数查询其他信息，例如 HardwareID 和描述。
这是我的代码。
别忘了
using System.Runtime.InteropServices;
各种 GUID 和属性的常量
public const uint SPDRP_DEVICEDESC = (0x00000000); // DeviceDesc (R/W)
public const uint SPDRP_HARDWAREID = (0x00000001); // HardwareID (R/W)
public const uint SPDRP_COMPATIBLEIDS = (0x00000002); // CompatibleIDs (R/W)
public const uint SPDRP_UNUSED0 = (0x00000003); // unused
public const uint SPDRP_SERVICE = (0x00000004); // Service (R/W)
public const uint SPDRP_UNUSED1 = (0x00000005); // unused
public const uint SPDRP_UNUSED2 = (0x00000006); // unused
public const uint SPDRP_CLASS = (0x00000007); // Class (R--tied to ClassGUID)
public const uint SPDRP_CLASSGUID = (0x00000008); // ClassGUID (R/W)
public const uint SPDRP_DRIVER = (0x00000009); // Driver (R/W)
public const uint SPDRP_CONFIGFLAGS = (0x0000000A); // ConfigFlags (R/W)
public const uint SPDRP_MFG = (0x0000000B); // Mfg (R/W)
public const uint SPDRP_FRIENDLYNAME = (0x0000000C); // FriendlyName (R/W)
public const uint SPDRP_LOCATION_INFORMATION = (0x0000000D); // LocationInformation (R/W)
public const uint SPDRP_PHYSICAL_DEVICE_OBJECT_NAME = (0x0000000E); // PhysicalDeviceObjectName (R)
public const uint SPDRP_CAPABILITIES = (0x0000000F); // Capabilities (R)
public const uint SPDRP_UI_NUMBER = (0x00000010); // UiNumber (R)
public const uint SPDRP_UPPERFILTERS = (0x00000011); // UpperFilters (R/W)
public const uint SPDRP_LOWERFILTERS = (0x00000012); // LowerFilters (R/W)
public const uint SPDRP_BUSTYPEGUID = (0x00000013); // BusTypeGUID (R)
public const uint SPDRP_LEGACYBUSTYPE = (0x00000014); // LegacyBusType (R)
public const uint SPDRP_BUSNUMBER = (0x00000015); // BusNumber (R)
public const uint SPDRP_ENUMERATOR_NAME = (0x00000016); // Enumerator Name (R)
public const uint SPDRP_SECURITY = (0x00000017); // Security (R/W, binary form)
public const uint SPDRP_SECURITY_SDS = (0x00000018); // Security (W, SDS form)
public const uint SPDRP_DEVTYPE = (0x00000019); // Device Type (R/W)
public const uint SPDRP_EXCLUSIVE = (0x0000001A); // Device is exclusive-access (R/W)
public const uint SPDRP_CHARACTERISTICS = (0x0000001B); // Device Characteristics (R/W)
public const uint SPDRP_ADDRESS = (0x0000001C); // Device Address (R)
public const uint SPDRP_UI_NUMBER_DESC_FORMAT = (0X0000001D); // UiNumberDescFormat (R/W)
public const uint SPDRP_DEVICE_POWER_DATA = (0x0000001E); // Device Power Data (R)
public const uint SPDRP_REMOVAL_POLICY = (0x0000001F); // Removal Policy (R)
public const uint SPDRP_REMOVAL_POLICY_HW_DEFAULT = (0x00000020); // Hardware Removal Policy (R)
public const uint SPDRP_REMOVAL_POLICY_OVERRIDE = (0x00000021); // Removal Policy Override (RW)
public const uint SPDRP_INSTALL_STATE = (0x00000022); // Device Install State (R)
public const uint SPDRP_LOCATION_PATHS = (0x00000023); // Device Location Paths (R)
public const uint SPDRP_BASE_CONTAINERID = (0x00000024); // Base ContainerID (R)
public const uint SPDRP_MAXIMUM_PROPERTY = (0x00000025); // Upper bound on ordinals
public const string GUID_DEVINTERFACE_USB_HUB = "f18a0e88-c30c-11d0-8815-00a0c906bed8";
public const string GUID_DEVINTERFACE_USB_DEVICE = "A5DCBF10-6530-11D2-901F-00C04FB951ED";
public const string GUID_DEVINTERFACE_USB_HOST_CONTROLLER = "3ABF6F2D-71C4-462a-8A92-1E6861E6AF27";
public const string GUID_USB_WMI_STD_DATA = "4E623B20-CB14-11D1-B331-00A0C959BBD2";
public const string GUID_USB_WMI_STD_NOTIFICATION = "4E623B20-CB14-11D1-B331-00A0C959BBD2";
public const string GUID_USB_WMI_DEVICE_PERF_INFO = "66C1AA3C-499F-49a0-A9A5-61E2359F6407";
public const string GUID_USB_WMI_NODE_INFO = "9C179357-DC7A-4f41-B66B-323B9DDCB5B1";
public const string GUID_USB_WMI_TRACING = "3a61881b-b4e6-4bf9-ae0f-3cd8f394e52f";
public const string GUID_USB_TRANSFER_TRACING = "681EB8AA-403D-452c-9F8A-F0616FAC9540";
public const string GUID_USB_PERFORMANCE_TRACING = "D5DE77A6-6AE9-425c-B1E2-F5615FD348A9";
public const string GUID_USB_WMI_SURPRISE_REMOVAL_NOTIFICATION = "9BBBF831-A2F2-43B4-96D1-86944B5914B3";
结构和枚举：
public enum DEVICE_POWER_STATE
PowerDeviceUnspecified,
PowerDeviceD0,
PowerDeviceD1,
PowerDeviceD2,
PowerDeviceD3,
PowerDeviceMaximum
public enum SYSTEM_POWER_STATE
PowerSystemUnspecified,
PowerSystemWorking,
PowerSystemSleeping1,
PowerSystemSleeping2,
PowerSystemSleeping3,
PowerSystemHibernate,
PowerSystemShutdown,
PowerSystemMaximum
[StructLayout(LayoutKind.Sequential, Pack = 8)]
public struct SP_DEVINFO_DATA
public UInt32 cbSize;
public Guid ClassGuid;
public UInt32 DevInst;
public IntPtr Reserved;
[StructLayout(LayoutKind.Sequential, Pack = 8)]
public struct CM_POWER_DATA
public uint PD_Size;
public DEVICE_POWER_STATE PD_MostRecentPowerState;
public uint PD_Capabilities;
public uint PD_D1Latency;
public uint PD_D2Latency;
public uint PD_D3Latency;
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 7)]
public DEVICE_POWER_STATE[] PD_PowerStateMapping;
public SYSTEM_POWER_STATE PD_DeepestSystemWake;
DllImports
[DllImport("setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern bool SetupDiGetDeviceRegistryPropertyA(
IntPtr DeviceInfoSet,
ref SP_DEVINFO_DATA DeviceInfoData,
uint Property,
out RegistryDataType PropertyRegDataType,
byte[] PropertyBuffer,
//ref CM_POWER_DATA PropertyBuffer,
uint PropertyBufferSize,
out UInt32 RequiredSize
);
[DllImport("setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr SetupDiGetClassDevsA(
ref Guid ClassGuid,
[MarshalAs(UnmanagedType.LPTStr)] string Enumerator,
IntPtr hwndParent,
uint Flags
);
[DllImport("setupapi.dll", SetLastError=true)]
private static extern bool SetupDiEnumDeviceInfo(
IntPtr DeviceInfoSet,
uint MemberIndex,
ref SP_DEVINFO_DATA DeviceInfoData
);
各种功能，使检索更精美，更易于使用。主要的和我上面描述的一个是第一个 - GetInfoWithSetupDi。 （您需要将 GUID_DEVINTERFACE_USB_DEVICE 传递给它。）
/// <summary>
/// Gets information about devices in the device class including power state.
/// </summary>
/// <param name="classGuid">The GUID of the class in which to get information about devices from.</param>
/// <returns></returns>
public static List<DeviceInfo> GetInfoWithSetupDi(Guid classGuid)
List<DeviceInfo> deviceInfos = new List<DeviceInfo>();
IntPtr deviceInfoSet = SetupDiGetClassDevsA(ref classGuid, null, IntPtr.Zero, 0x00000002 | 0x00000010);
uint index = 0;
int error = 0;
while (error == 0)
DeviceInfo curDevice = new DeviceInfo
//Initializing SP_DEVINFO_DATA to be passed to SetupDiEnumDeviceInfo.
deviceInfoData = new SP_DEVINFO_DATA
cbSize = 28
;
//Retrieves the information about the specified device.
bool success = SetupDiEnumDeviceInfo(deviceInfoSet, index, ref curDevice.deviceInfoData);
index++;
error = Marshal.GetLastWin32Error();
if (error == 259)
break;
if (!success)
throw new Exception("Native method call error: " + error.ToString());
//Only add device after it was at least successfully retrieved.
deviceInfos.Add(curDevice);
//Retrieving individual information.
RegistryData localGetData(uint property) => GetData(deviceInfoSet, curDevice.deviceInfoData, property);
curDevice.hardwareId = (string[]) localGetData(SPDRP_HARDWAREID).parsed;
try
curDevice.description = (string)localGetData(SPDRP_DEVICEDESC).parsed;
catch
curDevice.description = "Description not set.";
curDevice.cmPowerData = MarshallingUtils.FromBytes<CM_POWER_DATA>(
localGetData(SPDRP_DEVICE_POWER_DATA).data
);
return deviceInfos;
/// <summary>
/// Gets the required size in bytes for the given property.
/// </summary>
/// <param name="deviceInfoSet">A handle to the set of devices.</param>
/// <param name="property">The property for which the get the required size.</param>
private static uint GetRequiredSize(IntPtr deviceInfoSet, uint Property)
SP_DEVINFO_DATA deviceInfoData = new SP_DEVINFO_DATA
cbSize = 28
;
ThrowErrorIfNotSuccessful(SetupDiEnumDeviceInfo(deviceInfoSet, 0, ref deviceInfoData));
return GetRequiredSize(deviceInfoSet, Property, deviceInfoData);
/// <summary>
/// Gets the required size in bytes for the given property.
/// </summary>
/// <param name="deviceInfoSet">A handle to the set of devices.</param>
/// <param name="property">The property for which the get the required size.</param>
/// <param name="deviceInfoData">Info of a device.</param>
/// <returns></returns>
private static uint GetRequiredSize(IntPtr deviceInfoSet, uint property, SP_DEVINFO_DATA deviceInfoData)
ThrowErrorIfNotSuccessful(
SetupDiGetDeviceRegistryPropertyA(
deviceInfoSet,
ref deviceInfoData,
property,
out RegistryDataType type,
new byte[1000],
1000,
out uint size)
);
return size;
/// <summary>
/// Gets the property using SetupDi of the device on the given index in the given device class.
/// </summary>
/// <param name="classGuid">The GUID of the device class.</param>
/// <param name="index">The index of the device.</param>
/// <param name="property">The property to retrieve.</param>
/// <returns></returns>
public static RegistryData GetData(Guid classGuid, uint index, uint property)
IntPtr deviceInfoSet = SetupDiGetClassDevsA(ref classGuid, null, IntPtr.Zero, 0x00000002 | 0x00000010);
SP_DEVINFO_DATA deviceInfoData = new SP_DEVINFO_DATA
cbSize = 28
;
ThrowErrorIfNotSuccessful(SetupDiEnumDeviceInfo(deviceInfoSet, index, ref deviceInfoData));
return GetData(deviceInfoSet, deviceInfoData, property);
/// <summary>
/// Gets the specified property using SetupDi of the device described in deviceInfoData in the given device info set.
/// The size is retrieved automatically.
/// </summary>
/// <param name="deviceInfoSet">A handle to the device info set.</param>
/// <param name="deviceInfoData">Description of the device.</param>
/// <param name="property">The property to retrieve.</param>
/// <returns></returns>
public static RegistryData GetData(IntPtr deviceInfoSet, SP_DEVINFO_DATA deviceInfoData, uint property)
uint size = GetRequiredSize(deviceInfoSet, property, deviceInfoData);
return GetData(deviceInfoSet, deviceInfoData, property, size);
/// <summary>
/// Gets the specified property using SetupDi of the device described in deviceInfoData in the given device info set.
/// </summary>
/// <param name="deviceInfoSet">A handle to the device info set.</param>
/// <param name="deviceInfoData">Description of the device.</param>
/// <param name="property">The property to retrieve.</param>
/// <returns></returns>
public static RegistryData GetData(IntPtr deviceInfoSet, SP_DEVINFO_DATA deviceInfoData, uint property, uint size)
byte[] data = new byte[size];
ThrowErrorIfNotSuccessful(
SetupDiGetDeviceRegistryPropertyA(
deviceInfoSet,
ref deviceInfoData,
property,
out RegistryDataType type,
data,
size,
out uint dummysize)
);
return new RegistryData(type, data);
/// <summary>
/// Method used to wrap native DLL calls. Throws the last system error when the call is unsuccessful.
/// </summary>
/// <param name="success">Return value of the native method. ( Usually used as ThrowErrorIfNotSuccessful(MethodCall()); )</param>
private static void ThrowErrorIfNotSuccessful(bool success)
if (!success)
throw new Exception("Native method call error: " + Marshal.GetLastWin32Error().ToString());
字节数组的通用版本上面提到的结构解析器。
public static class MarshallingUtils
public static byte[] GetBytes<T>(T str) where T : struct
int size = Marshal.SizeOf(str);
byte[] arr = new byte[size];
IntPtr ptr = Marshal.AllocHGlobal(size);
Marshal.StructureToPtr(str, ptr, true);
Marshal.Copy(ptr, arr, 0, size);
Marshal.FreeHGlobal(ptr);
return arr;
public static T FromBytes<T>(byte[] arr) where T : struct
T str = new T();
int size = Marshal.SizeOf(str);
IntPtr ptr = Marshal.AllocHGlobal(size);
Marshal.Copy(arr, 0, ptr, size);
str = (T)Marshal.PtrToStructure(ptr, str.GetType());
Marshal.FreeHGlobal(ptr);
return str;
用于解析检索到的注册表数据的帮助类。
public struct RegistryData
public readonly RegistryDataType type;
public readonly byte[] data;
public readonly object parsed;
public RegistryData(RegistryDataType type, byte[] data)
this.type = type;
this.data = data;
this.parsed = ParseData(type, data);
public static string ParseString(byte[] data)
string s = "";
foreach (byte b in data)
if (b == 0)
break;
s += (char)b;
return s;
public static string[] ParseMultiString(byte[] data)
List<string> list = new List<string>();
string current = "";
bool terminator = false;
foreach (byte b in data)
if (b == 0)
if (terminator)
break;
else
terminator = true;
//Start a new string.
list.Add(current);
current = "";
else
terminator = false;
current += (char)b;
return list.ToArray();
private static object ParseData(RegistryDataType type, byte[] data)
switch (type)
case RegistryDataType.REG_SZ:
return (object)ParseString(data);
case RegistryDataType.REG_MULTI_SZ:
return (object)ParseMultiString(data);
default: return null;
public override string ToString()
switch (type)
case RegistryDataType.REG_SZ: return (string)parsed;
case RegistryDataType.REG_MULTI_SZ: return String.Join(";", (List<string>)parsed);
default: return null;
以及检索到的注册表数据类型的最后一个枚举。
public enum RegistryDataType
REG_NONE = (0), // No value type
REG_SZ = (1), // Unicode nul terminated string
REG_EXPAND_SZ = (2), // Unicode nul terminated string
// = (with environment variable references)
REG_BINARY = (3), // Free form binary
//REG_DWORD = (4), // 32-bit number
REG_DWORD_LITTLE_ENDIAN = (4), // 32-bit number = (same as REG_DWORD)
REG_DWORD_BIG_ENDIAN = (5), // 32-bit number
REG_LINK = (6), // Symbolic Link = (unicode)
REG_MULTI_SZ = (7), // Multiple Unicode strings
REG_RESOURCE_LIST = (8), // Resource list in the resource map
REG_FULL_RESOURCE_DESCRIPTOR = (9), // Resource list in the hardware description
REG_RESOURCE_REQUIREMENTS_LIST = (10),
//REG_QWORD = (11), // 64-bit number
REG_QWORD_LITTLE_ENDIAN = (11), // 64-bit number = (same as REG_QWORD)
还有一个保存信息的类。
public class DeviceInfo
public SP_DEVINFO_DATA deviceInfoData;
public string[] hardwareId;
public string description;
public CM_POWER_DATA cmPowerData;
【讨论】：
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