I am trying to figure out how to detect if a drive is a mass storage device. I can get the drive letters but cannot figure out how to detect what sort of device it is. I am trying to detect if a Garmin GPS receiver is connected to a PC in mass storage mode.
You can use the WMI for this task, exist several classes which can help you to determine that information, start with the Win32_USBHub
checking for the value Mass Storage Device
in the the property Description, also take a look in the Win32_PNPEntity
class. If you don't have experience accesing the WMI from Delphi, try using the Wmi delphi code creator
UPDATE
To associate the values returned by the Win32_USBHub or Win32_USBControllerDevice WMI classes with a Disk Drive letter, you must follow the next steps
DeviceID
extracted of the dependent
property of each returned instance(record) check the Win32_PnPEntity class loinked to a Win32_DiskDrive using a WQL sentence like so : ASSOCIATORS OF {Win32_PnPEntity.DeviceID="DeviceID"} WHERE ResultClass = Win32_DiskDrive
Check this sample code
{$APPTYPE CONSOLE}
{$R *.res}
uses
Types,
StrUtils,
SysUtils,
ActiveX,
ComObj,
Variants;
procedure ScanUSBPnpDevices;
const
wbemFlagForwardOnly = $00000020;
var
FSWbemLocator : OLEVariant;
objWMIService : OLEVariant;
USBControllerDevices: OLEVariant;
USBControllerDevice : OLEVariant;
EnumUSBDevice : IEnumvariant;
PnPEntities : OLEVariant;
PnPEntity : OLEVariant;
EnumPnPEntity : IEnumvariant;
DiskDrives : OLEVariant;
DiskDrive : OLEVariant;
EnumDiskDrive : IEnumvariant;
DiskPartitions : OLEVariant;
DiskPartition : OLEVariant;
EnumDiskPartition : IEnumvariant;
iValue : LongWord;
DeviceID : string;
DiskDeviceID : string;
DiskPartID : string;
StringDynArray : TStringDynArray;
begin;
FSWbemLocator := CreateOleObject('WbemScripting.SWbemLocator');
objWMIService := FSWbemLocator.ConnectServer('localhost', 'root\CIMV2', '', '');
//This will scan all the usb device, you can filter this WQL sentece using any property of this class, to speed-up the process.
USBControllerDevices := objWMIService.ExecQuery('SELECT Dependent FROM Win32_USBControllerDevice','WQL',wbemFlagForwardOnly);
EnumUSBDEvice := IUnknown(USBControllerDevices._NewEnum) as IEnumVariant;
while EnumUSBDEvice.Next(1, USBControllerDevice, iValue) = 0 do
begin
StringDynArray:=SplitString(USBControllerDevice.Dependent, '=');
DeviceID:=StringDynArray[1];
Writeln(Format('USB Controller Device Device ID %s',[DeviceID]));
PnPEntities := objWMIService.ExecQuery(Format('ASSOCIATORS OF {Win32_PnPEntity.DeviceID=%s} WHERE ResultClass = Win32_DiskDrive',[DeviceID]),'WQL',wbemFlagForwardOnly);
EnumPnPEntity := IUnknown(PnPEntities._NewEnum) as IEnumVariant;
while EnumPnPEntity.Next(1, PnPEntity, iValue) = 0 do
begin
//Escape the `\` chars in the DeviceID value because the '\' is a reserved character in WMI.
DiskDeviceID := PnPEntity.DeviceId;
Writeln(Format(' Disk Drive Device ID %s',[DiskDeviceID]));
DiskDeviceID := StringReplace(DiskDeviceID,'\','\\',[rfReplaceAll]);;
DiskDrives := objWMIService.ExecQuery(Format('ASSOCIATORS OF {Win32_DiskDrive.DeviceID="%s"} WHERE AssocClass = Win32_DiskDriveToDiskPartition',[DiskDeviceID]),'WQL',wbemFlagForwardOnly);
EnumDiskDrive := IUnknown(DiskDrives._NewEnum) as IEnumVariant;
while EnumDiskDrive.Next(1, DiskDrive, iValue) = 0 do
begin
DiskPartID:=DiskDrive.deviceID;
Writeln(Format(' Disk Partition ID %s',[DiskPartID]));
DiskPartitions:=objWMIService.ExecQuery(Format('ASSOCIATORS OF {Win32_DiskPartition.DeviceID="%s"} WHERE AssocClass = Win32_LogicalDiskToPartition',[DiskPartID]),'WQL',wbemFlagForwardOnly);
EnumDiskPartition := IUnknown(DiskPartitions._NewEnum) as IEnumVariant;
while EnumDiskPartition.Next(1, DiskPartition, iValue) = 0 do
begin
Writeln(Format(' Drive Letter %s',[String(DiskPartition.DeviceID)]));
DiskPartition:=Unassigned;
end;
DiskDrive:=Unassigned;
end;
PnPEntity:=Unassigned;
end;
USBControllerDevice:=Unassigned;
end;
end;
begin
try
CoInitialize(nil);
try
ScanUSBPnpDevices;
finally
CoUninitialize;
end;
except
on E:Exception do
Writeln(E.Classname, ':', E.Message);
end;
Readln;
end.
Which will return some thing like this.
USB Controller Device Device ID "USBSTOR\\DISK&VEN_HP&PROD_V100W&REV_1.00\\3S980
62800DD&0"
Disk Drive Device ID \\.\PHYSICALDRIVE1
Disk Partition ID Disk #1, Partition #0
Drive Letter F: