使用安装程序 API 枚举监视器 pnp 设备 ID

Question

对于我的程序，我需要获取有关当前显示器的详细信息。在我的研究中，我遇到了这篇文章，其中讨论了链接System.Windows.Forms.Screen类及其EDID信息。起初，我尝试复制和粘贴使用 p/invoke 找到的代码，以提供所有必需的本机方法和结构，但它不起作用，只给了我一串？作为实例 ID。因此，我尝试使用 MSDN 资源，并再次使用 p/invoke 自己创建代码。这就是我想出的：

private static void Foo()
{
Guid DisplayGUID = new Guid(Bar.GUID_DEVINTERFACE_MONITOR);
IntPtr DisplaysHandle = Bar.SetupDiGetClassDevs(ref DisplayGUID, null, IntPtr.Zero, (uint)(Win32.DIGCF_PRESENT | Win32.DIGCF_DEVICEINTERFACE));
Bar.SP_DEVICE_INTERFACE_DATA Data = new Bar.SP_DEVICE_INTERFACE_DATA();
Data.cbSize = Marshal.SizeOf(Data);
for (uint id = 0; Bar.SetupDiEnumDeviceInterfaces(DisplaysHandle, IntPtr.Zero, ref DisplayGUID, id, ref Data); id++)
{
Bar.SP_DEVINFO_DATA SPDID = new Bar.SP_DEVINFO_DATA();
SPDID.cbSize = (uint)Marshal.SizeOf(SPDID);
Bar.SP_DEVICE_INTERFACE_DETAIL_DATA NDIDD = new Bar.SP_DEVICE_INTERFACE_DETAIL_DATA();
if (IntPtr.Size == 8) //64 bit
NDIDD.cbSize = 8;
else //32 bit
NDIDD.cbSize = 4 + Marshal.SystemDefaultCharSize;
uint requiredsize = 0;
uint buffer = Bar.BUFFER_SIZE;
if (Bar.SetupDiGetDeviceInterfaceDetail(DisplaysHandle, ref Data, ref NDIDD, buffer, ref requiredsize, ref SPDID))
{
uint size = 0;
Bar.CM_Get_Device_ID_Size(out size, SPDID.DevInst);
IntPtr ptrInstanceBuf = Marshal.AllocHGlobal((int)size);
Bar.CM_Get_Device_ID(SPDID.DevInst, ref ptrInstanceBuf, size);
string InstanceID = Marshal.PtrToStringAuto(ptrInstanceBuf);
Console.WriteLine("InstanceID: {0}", InstanceID);
Marshal.FreeHGlobal(ptrInstanceBuf);
Console.WriteLine("DevicePath: {0}n", NDIDD.DevicePath);
}
}
Bar.SetupDiDestroyDeviceInfoList(DisplaysHandle);
}
private class Bar
{
[DllImport("setupapi.dll", CharSet = CharSet.Auto)]
public static extern IntPtr SetupDiGetClassDevs(ref Guid ClassGuid, [MarshalAs(UnmanagedType.LPTStr)] string Enumerator, IntPtr hwndParent, uint Flags);
[DllImport("setupapi.dll", SetLastError = true)]
public static extern bool SetupDiDestroyDeviceInfoList(IntPtr DeviceInfoSet);
[DllImport(@"setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
public static extern Boolean SetupDiEnumDeviceInterfaces(IntPtr hDevInfo, IntPtr devInfo, ref Guid interfaceClassGuid, UInt32 memberIndex, ref SP_DEVICE_INTERFACE_DATA deviceInterfaceData);
[DllImport(@"setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
public static extern Boolean SetupDiGetDeviceInterfaceDetail(IntPtr hDevInfo, ref SP_DEVICE_INTERFACE_DATA deviceInterfaceData, ref SP_DEVICE_INTERFACE_DETAIL_DATA deviceInterfaceDetailData, UInt32 deviceInterfaceDetailDataSize, ref UInt32 requiredSize, ref SP_DEVINFO_DATA deviceInfoData);
[DllImport("setupapi.dll", SetLastError = true)]
public static extern int CM_Get_Device_ID_Size(out uint pulLen, UInt32 dnDevInst, int flags = 0);
[DllImport("setupapi.dll", SetLastError = true)]
public static extern int CM_Get_Device_ID(uint dnDevInst, ref IntPtr Buffer, uint BufferLen, int ulFlags = 0);
public const int BUFFER_SIZE = 168; //guess
public const string GUID_DEVINTERFACE_MONITOR = "{E6F07B5F-EE97-4a90-B076-33F57BF4EAA7}";
[Flags]
public enum DiGetClassFlags : uint
{
DIGCF_DEFAULT = 0x00000001,  // only valid with DIGCF_DEVICEINTERFACE
DIGCF_PRESENT = 0x00000002,
DIGCF_ALLCLASSES = 0x00000004,
DIGCF_PROFILE = 0x00000008,
DIGCF_DEVICEINTERFACE = 0x00000010,
}
[StructLayout(LayoutKind.Sequential)]
public struct SP_DEVICE_INTERFACE_DATA
{
public Int32 cbSize;
public Guid interfaceClassGuid;
public Int32 flags;
private UIntPtr reserved;
}
[StructLayout(LayoutKind.Sequential)]
public struct SP_DEVINFO_DATA
{
public uint cbSize;
public Guid classGuid;
public uint DevInst;
public IntPtr reserved;
}
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
public struct SP_DEVICE_INTERFACE_DETAIL_DATA
{
public int cbSize;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = BUFFER_SIZE)]
public string DevicePath;
}
}

我的代码编译并运行，但它没有给我所需的输出。

我正在寻找的输出是：

InstanceID: DISPLAYDELA00B5&786e6ca&0&UID1048832
DevicePath: \?display#dela00b#5&786e6ca&0&uid1048832#{e6f07b5f-ee97-4a90-b076-33f57bf4eaa7}

但这是我收到的输出：

InstanceID: l
DevicePath: \?display#dela00b#5&786e6ca&0&uid1048832#{e6f07b5f-ee97-4a90-b076-33f57bf4eaa7}

我的问题以导致实例ID无法正确输出的问题的形式出现。

Answer 1

原来我使用了错误的 p/invoke 签名。CM_Get_Device_ID应如下所示：

[DllImport("setupapi.dll", SetLastError = true)]
public static extern int CM_Get_Device_ID(uint dnDevInst, StringBuilder Buffer, int BufferLen, int ulFlags = 0);

还更新了使用代码：

StringBuilder IDBuffer = new StringBuilder((int)buffer);
Bar.CM_Get_Device_ID(SPDID.DevInst, IDBuffer, (int)buffer);
Console.WriteLine("InstanceID: {0}", IDBuffer.ToString());
Console.WriteLine("DevicePath: {0}n", NDIDD.DevicePath);