Delphi调用WMI读取USB设备的PID和VID

以下代码出自http://blog.csdn.net/hellogv/,引用请注明出处！

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 WMI(Windows®Management Instrumentation ) 非常强大，它可以以数据库的形式查询你的电脑的软件和硬件，在它的数据库里面，时刻保存着最新的软件信息和硬件信息，因此你可以用WMI来检测CUP主频、温度，读取WINDOWS的进程.........

  本文就介绍如何使用WMI读取USB设备的PID和VID码

 

Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,  Dialogs, StdCtrls, ExtCtrls,ActiveX, ComObj;procedure TForm1.Button2Click(Sender: TObject);varLocator: OleVariant;WMI: OleVariant;RET: OleVariant;Enum: IEnumVariant;Tmp: OleVariant;Value: Cardinal;begin;Locator := CreateOleObject('WbemScripting.SWbemLocator');WMI := Locator.ConnectServer('.', '', '', '');Ret := WMI.ExecQuery('SELECT * FROM Win32_USBHub');//这里Win32_USBHub为检测项，详见下表Enum:= IUnknown(RET._NewEnum) as IEnumVariant;while (Enum.Next(1, Tmp, Value) = S_OK) dobegin  if Tmp.Name='USB Mass Storage Device' then     ShowMessage('这个u盘的硬件特征码是'+Tmp.PNPDeviceID);//Tmp为检测到返回的数据集合，其中PNPDeviceID为集合中的对象，包含了PID和VID码end;end;Win32_USBHub只是冰山一角，常用的还有以下  "Win32_1394Controller"                ,  "Win32_BaseBoard"                     ,  "Win32_Battery"                       ,  "Win32_BIOS"                          ,  "Win32_Bus"                           ,  "Win32_CacheMemory"                   ,  "Win32_CDROMDrive"                    ,  "Win32_CurrentProbe"                  ,  "Win32_DesktopMonitor"                ,  "Win32_DeviceMemoryAddress"           ,  "Win32_DiskDrive"                     ,  "Win32_DisplayConfiguration"          ,  "Win32_DisplayControllerConfiguration",  "Win32_DMAChannel"                    ,  "Win32_Fan"                           ,  "Win32_FloppyController"              ,  "Win32_FloppyDrive"                   ,  "Win32_HeatPipe"                      ,  "Win32_IDEController"                 ,  "Win32_InfraredDevice"                ,  "Win32_IRQResource"                   ,  "Win32_Keyboard"                      ,  "Win32_MemoryArray"                   ,  "Win32_MemoryDevice"                  ,  "Win32_MotherboardDevice"             ,  "Win32_NetworkAdapter"                ,  "Win32_NetworkAdapterConfiguration"   ,  "Win32_OnBoardDevice"                 ,  "Win32_ParallelPort"                  ,  "Win32_PCMCIAController"              ,  "Win32_PhysicalMemory"                ,  "Win32_PhysicalMemoryArray"           ,  "Win32_PnPEntity"                     ,  "Win32_PointingDevice"                ,  "Win32_PortableBattery"               ,  "Win32_PortConnector"                 ,  "Win32_PortResource"                  ,  "Win32_POTSModem"                     ,  "Win32_PowerManagementEvent"          ,  "Win32_Printer"                       ,  "Win32_PrinterConfiguration"          ,  "Win32_PrintJob"                      ,  "Win32_Processor"                     ,  "Win32_Refrigeration"                 ,  "Win32_SerialPort"                    ,  "Win32_SerialPortConfiguration"       ,  "Win32_SMBIOSMemory"                  ,  "Win32_SoundDevice"                   ,  "Win32_SystemEnclosure"               ,  "Win32_SystemMemoryResource"          ,  "Win32_SystemSlot"                    ,  "Win32_TapeDrive"                     ,  "Win32_TemperatureProbe"              ,  "Win32_UninterruptiblePowerSupply"    ,  "Win32_USBController"                 ,  "Win32_VideoConfiguration"            ,  "Win32_VideoController"               ,  "Win32_VoltageProbe"                  ,